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diff --git a/northamerica b/northamerica new file mode 100644 index 0000000..bbfce49 --- /dev/null +++ b/northamerica @@ -0,0 +1,3627 @@ +# tzdb data for North and Central America and environs + +# This file is in the public domain, so clarified as of +# 2009-05-17 by Arthur David Olson. + +# also includes Central America and the Caribbean + +# This file is by no means authoritative; if you think you know better, +# go ahead and edit the file (and please send any changes to +# tz@iana.org for general use in the future). For more, please see +# the file CONTRIBUTING in the tz distribution. + +# From Paul Eggert (1999-03-22): +# A reliable and entertaining source about time zones is +# Derek Howse, Greenwich time and longitude, Philip Wilson Publishers (1997). + +############################################################################### + +# United States + +# From Paul Eggert (1999-03-31): +# Howse writes (pp 121-125) that time zones were invented by +# Professor Charles Ferdinand Dowd (1825-1904), +# Principal of Temple Grove Ladies' Seminary (Saratoga Springs, NY). +# His pamphlet "A System of National Time for Railroads" (1870) +# was the result of his proposals at the Convention of Railroad Trunk Lines +# in New York City (1869-10). His 1870 proposal was based on Washington, DC, +# but in 1872-05 he moved the proposed origin to Greenwich. + +# From Paul Eggert (2018-03-20): +# Dowd's proposal left many details unresolved, such as where to draw +# lines between time zones. The key individual who made time zones +# work in the US was William Frederick Allen - railway engineer, +# managing editor of the Travelers' Guide, and secretary of the +# General Time Convention, a railway standardization group. Allen +# spent months in dialogs with scientific and railway leaders, +# developed a workable plan to institute time zones, and presented it +# to the General Time Convention on 1883-04-11, saying that his plan +# meant "local time would be practically abolished" - a plus for +# railway scheduling. By the next convention on 1883-10-11 nearly all +# railroads had agreed and it took effect on 1883-11-18. That Sunday +# was called the "day of two noons", as some locations observed noon +# twice. Allen witnessed the transition in New York City, writing: +# +# I heard the bells of St. Paul's strike on the old time. Four +# minutes later, obedient to the electrical signal from the Naval +# Observatory ... the time-ball made its rapid descent, the chimes +# of old Trinity rang twelve measured strokes, and local time was +# abandoned, probably forever. +# +# Most of the US soon followed suit. See: +# Bartky IR. The adoption of standard time. Technol Cult 1989 Jan;30(1):25-56. +# https://dx.doi.org/10.2307/3105430 + +# From Paul Eggert (2005-04-16): +# That 1883 transition occurred at 12:00 new time, not at 12:00 old time. +# See p 46 of David Prerau, Seize the daylight, Thunder's Mouth Press (2005). + +# From Paul Eggert (2006-03-22): +# A good source for time zone historical data in the US is +# Thomas G. Shanks, The American Atlas (5th edition), +# San Diego: ACS Publications, Inc. (1991). +# Make sure you have the errata sheet; the book is somewhat useless without it. +# It is the source for most of the pre-1991 US entries below. + +# From Paul Eggert (2001-03-06): +# Daylight Saving Time was first suggested as a joke by Benjamin Franklin +# in his whimsical essay "An Economical Project for Diminishing the Cost +# of Light" published in the Journal de Paris (1784-04-26). +# Not everyone is happy with the results: +# +# I don't really care how time is reckoned so long as there is some +# agreement about it, but I object to being told that I am saving +# daylight when my reason tells me that I am doing nothing of the kind. +# I even object to the implication that I am wasting something +# valuable if I stay in bed after the sun has risen. As an admirer +# of moonlight I resent the bossy insistence of those who want to +# reduce my time for enjoying it. At the back of the Daylight Saving +# scheme I detect the bony, blue-fingered hand of Puritanism, eager +# to push people into bed earlier, and get them up earlier, to make +# them healthy, wealthy and wise in spite of themselves. +# +# -- Robertson Davies, The diary of Samuel Marchbanks, +# Clarke, Irwin (1947), XIX, Sunday +# +# For more about the first ten years of DST in the United States, see +# Robert Garland, Ten years of daylight saving from the Pittsburgh standpoint +# (Carnegie Library of Pittsburgh, 1927). +# https://web.archive.org/web/20160517155308/http://www.clpgh.org/exhibit/dst.html +# +# Shanks says that DST was called "War Time" in the US in 1918 and 1919. +# However, DST was imposed by the Standard Time Act of 1918, which +# was the first nationwide legal time standard, and apparently +# time was just called "Standard Time" or "Daylight Saving Time". + +# From Paul Eggert (2019-06-04): +# Here is the legal basis for the US federal rules. +# * Public Law 65-106 (1918-03-19) implemented standard and daylight saving +# time for the first time across the US, springing forward on March's last +# Sunday and falling back on October's last Sunday. +# https://www.loc.gov/law/help/statutes-at-large/65th-congress/session-2/c65s2ch24.pdf +# * Public Law 66-40 (1919-08-20) repealed DST on October 1919's last Sunday. +# https://www.loc.gov/law/help/statutes-at-large/66th-congress/session-1/c66s1ch51.pdf +# * Public Law 77-403 (1942-01-20) started wartime DST on 1942-02-09. +# https://www.loc.gov/law/help/statutes-at-large/77th-congress/session-2/c77s2ch7.pdf +# * Public Law 79-187 (1945-09-25) ended wartime DST on 1945-09-30. +# https://www.loc.gov/law/help/statutes-at-large/79th-congress/session-1/c79s1ch388.pdf +# * Public Law 89-387 (1966-04-13) reinstituted a national standard for DST, +# from April's last Sunday to October's last Sunday, effective 1967. +# https://www.govinfo.gov/content/pkg/STATUTE-80/pdf/STATUTE-80-Pg107.pdf +# * Public Law 93-182 (1973-12-15) moved the 1974 spring-forward to 01-06. +# https://www.govinfo.gov/content/pkg/STATUTE-87/pdf/STATUTE-87-Pg707.pdf +# * Public Law 93-434 (1974-10-05) moved the 1975 spring-forward to +# February's last Sunday. +# https://www.govinfo.gov/content/pkg/STATUTE-88/pdf/STATUTE-88-Pg1209.pdf +# * Public Law 99-359 (1986-07-08) moved the spring-forward to April's first +# Sunday. +# https://www.govinfo.gov/content/pkg/STATUTE-100/pdf/STATUTE-100-Pg764.pdf +# * Public Law 109-58 (2005-08-08), effective 2007, moved the spring-forward +# to March's second Sunday and the fall-back to November's first Sunday. +# https://www.govinfo.gov/content/pkg/PLAW-109publ58/pdf/PLAW-109publ58.pdf +# All transitions are at 02:00 local time. + +# From Arthur David Olson: +# Before the Uniform Time Act of 1966 took effect in 1967, observance of +# Daylight Saving Time in the US was by local option, except during wartime. + +# From Arthur David Olson (2000-09-25): +# Last night I heard part of a rebroadcast of a 1945 Arch Oboler radio drama. +# In the introduction, Oboler spoke of "Eastern Peace Time." +# An AltaVista search turned up: +# https://web.archive.org/web/20000926032210/http://rowayton.org/rhs/hstaug45.html +# "When the time is announced over the radio now, it is 'Eastern Peace +# Time' instead of the old familiar 'Eastern War Time.' Peace is wonderful." +# (August 1945) by way of confirmation. +# +# From Paul Eggert (2017-09-23): +# This was the V-J Day issue of the Clamdigger, a Rowayton, CT newsletter. + +# From Joseph Gallant citing +# George H. Douglas, _The Early Days of Radio Broadcasting_ (1987): +# At 7 P.M. (Eastern War Time) [on 1945-08-14], the networks were set +# to switch to London for Attlee's address, but the American people +# never got to hear his speech live. According to one press account, +# CBS' Bob Trout was first to announce the word of Japan's surrender, +# but a few seconds later, NBC, ABC and Mutual also flashed the word +# of surrender, all of whom interrupting the bells of Big Ben in +# London which were to precede Mr. Attlee's speech. + +# From Paul Eggert (2003-02-09): It was Robert St John, not Bob Trout. From +# Myrna Oliver's obituary of St John on page B16 of today's Los Angeles Times: +# +# ... a war-weary U.S. clung to radios, awaiting word of Japan's surrender. +# Any announcement from Asia would reach St. John's New York newsroom on a +# wire service teletype machine, which had prescribed signals for major news. +# Associated Press, for example, would ring five bells before spewing out +# typed copy of an important story, and 10 bells for news "of transcendental +# importance." +# +# On Aug. 14, stalling while talking steadily into the NBC networks' open +# microphone, St. John heard five bells and waited only to hear a sixth bell, +# before announcing confidently: "Ladies and gentlemen, World War II is over. +# The Japanese have agreed to our surrender terms." +# +# He had scored a 20-second scoop on other broadcasters. + +# From Arthur David Olson (2005-08-22): +# Paul has been careful to use the "US" rules only in those locations +# that are part of the United States; this reflects the real scope of +# U.S. government action. So even though the "US" rules have changed +# in the latest release, other countries won't be affected. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule US 1918 1919 - Mar lastSun 2:00 1:00 D +Rule US 1918 1919 - Oct lastSun 2:00 0 S +Rule US 1942 only - Feb 9 2:00 1:00 W # War +Rule US 1945 only - Aug 14 23:00u 1:00 P # Peace +Rule US 1945 only - Sep 30 2:00 0 S +Rule US 1967 2006 - Oct lastSun 2:00 0 S +Rule US 1967 1973 - Apr lastSun 2:00 1:00 D +Rule US 1974 only - Jan 6 2:00 1:00 D +Rule US 1975 only - Feb lastSun 2:00 1:00 D +Rule US 1976 1986 - Apr lastSun 2:00 1:00 D +Rule US 1987 2006 - Apr Sun>=1 2:00 1:00 D +Rule US 2007 max - Mar Sun>=8 2:00 1:00 D +Rule US 2007 max - Nov Sun>=1 2:00 0 S + +# From Arthur David Olson, 2005-12-19 +# We generate the files specified below to guard against old files with +# obsolete information being left in the time zone binary directory. +# We limit the list to names that have appeared in previous versions of +# this time zone package. +# We do these as separate Zones rather than as Links to avoid problems if +# a particular place changes whether it observes DST. +# We put these specifications here in the northamerica file both to +# increase the chances that they'll actually get compiled and to +# avoid the need to duplicate the US rules in another file. + +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone EST -5:00 - EST +Zone MST -7:00 - MST +Zone HST -10:00 - HST +Zone EST5EDT -5:00 US E%sT +Zone CST6CDT -6:00 US C%sT +Zone MST7MDT -7:00 US M%sT +Zone PST8PDT -8:00 US P%sT + +# From U. S. Naval Observatory (1989-01-19): +# USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON +# USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30 +# USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON +# USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30 +# USA MOUNTAIN 7 H BEHIND UTC DENVER +# USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30 +# USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO +# USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30 +# USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST) +# USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT) +# USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W +# USA " 9 H BEHIND UTC APR 3 - OCT 30 +# USA HAWAII 10 H BEHIND UTC +# USA BERING 11 H BEHIND UTC SAMOA, MIDWAY + +# From Arthur David Olson (1989-01-21): +# The above dates are for 1988. +# Note the "AKST" and "AKDT" abbreviations, the claim that there's +# no DST in Samoa, and the claim that there is DST in Alaska and the +# Aleutians. + +# From Arthur David Olson (1988-02-13): +# Legal standard time zone names, from United States Code (1982 Edition and +# Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names +# up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966 +# took effect), as explained in sections 263 and 261: +# (none) +# United States standard eastern time +# United States standard mountain time +# United States standard central time +# United States standard Pacific time +# (none) +# United States standard Alaska time +# (none) +# Next, names from 1967-04-01 until 1983-11-30 (the date for +# public law 98-181): +# Atlantic standard time +# eastern standard time +# central standard time +# mountain standard time +# Pacific standard time +# Yukon standard time +# Alaska-Hawaii standard time +# Bering standard time +# And after 1983-11-30: +# Atlantic standard time +# eastern standard time +# central standard time +# mountain standard time +# Pacific standard time +# Alaska standard time +# Hawaii-Aleutian standard time +# Samoa standard time +# The law doesn't give abbreviations. +# +# From Paul Eggert (2016-12-19): +# Here are URLs for the 1918 and 1966 legislation: +# http://uscode.house.gov/statviewer.htm?volume=40&page=451 +# http://uscode.house.gov/statviewer.htm?volume=80&page=108 +# Although the 1918 names were officially "United States Standard +# Eastern Time" and similarly for "Central", "Mountain", "Pacific", +# and "Alaska", in practice "Standard" was placed just before "Time", +# as codified in 1966. In practice, Alaska time was abbreviated "AST" +# before 1968. Summarizing the 1967 name changes: +# 1918 names 1967 names +# -08 Standard Pacific Time (PST) Pacific standard time (PST) +# -09 (unofficial) Yukon (YST) Yukon standard time (YST) +# -10 Standard Alaska Time (AST) Alaska-Hawaii standard time (AHST) +# -11 (unofficial) Nome (NST) Bering standard time (BST) +# +# From Paul Eggert (2023-01-23), from a 2001-01-08 heads-up from Rives McDow: +# Public law 106-564 (2000-12-23) introduced "Chamorro standard time" +# for time in Guam and the Northern Marianas. See the file "australasia". +# Also see 15 U.S.C. §263 <https://www.law.cornell.edu/uscode/text/15/263>. +# +# From Paul Eggert (2015-04-17): +# HST and HDT are standardized abbreviations for Hawaii-Aleutian +# standard and daylight times. See section 9.47 (p 234) of the +# U.S. Government Printing Office Style Manual (2008) +# https://www.gpo.gov/fdsys/pkg/GPO-STYLEMANUAL-2008/pdf/GPO-STYLEMANUAL-2008.pdf + +# From Arthur David Olson, 2005-08-09 +# The following was signed into law on 2005-08-08. +# +# H.R. 6, Energy Policy Act of 2005, SEC. 110. DAYLIGHT SAVINGS. +# (a) Amendment.--Section 3(a) of the Uniform Time Act of 1966 (15 +# U.S.C. 260a(a)) is amended-- +# (1) by striking "first Sunday of April" and inserting "second +# Sunday of March"; and +# (2) by striking "last Sunday of October" and inserting "first +# Sunday of November'. +# (b) Effective Date.--Subsection (a) shall take effect 1 year after the +# date of enactment of this Act or March 1, 2007, whichever is later. +# (c) Report to Congress.--Not later than 9 months after the effective +# date stated in subsection (b), the Secretary shall report to Congress +# on the impact of this section on energy consumption in the United +# States. +# (d) Right to Revert.--Congress retains the right to revert the +# Daylight Saving Time back to the 2005 time schedules once the +# Department study is complete. + +# US eastern time, represented by New York + +# Connecticut, Delaware, District of Columbia, most of Florida, +# Georgia, southeast Indiana (Dearborn and Ohio counties), eastern Kentucky +# (except America/Kentucky/Louisville below), Maine, Maryland, Massachusetts, +# New Hampshire, New Jersey, New York, North Carolina, Ohio, +# Pennsylvania, Rhode Island, South Carolina, eastern Tennessee, +# Vermont, Virginia, West Virginia + +# From Dave Cantor (2004-11-02): +# Early this summer I had the occasion to visit the Mount Washington +# Observatory weather station atop (of course!) Mount Washington [, NH].... +# One of the staff members said that the station was on Eastern Standard Time +# and didn't change their clocks for Daylight Saving ... so that their +# reports will always have times which are 5 hours behind UTC. + +# From Paul Eggert (2005-08-26): +# According to today's Huntsville Times +# http://www.al.com/news/huntsvilletimes/index.ssf?/base/news/1125047783228320.xml&coll=1 +# a few towns on Alabama's "eastern border with Georgia, such as Phenix City +# in Russell County, Lanett in Chambers County and some towns in Lee County, +# set their watches and clocks on Eastern time." It quotes H.H. "Bubba" +# Roberts, city administrator in Phenix City. as saying "We are in the Central +# time zone, but we do go by the Eastern time zone because so many people work +# in Columbus." +# +# From Paul Eggert (2017-02-22): +# Four cities are involved. The two not mentioned above are Smiths Station +# and Valley. Barbara Brooks, Valley's assistant treasurer, heard it started +# because West Point Pepperell textile mills were in Alabama while the +# corporate office was in Georgia, and residents voted to keep Eastern +# time even after the mills closed. See: Kazek K. Did you know which +# Alabama towns are in a different time zone? al.com 2017-02-06. +# http://www.al.com/living/index.ssf/2017/02/do_you_know_which_alabama_town.html + +# From Paul Eggert (2014-09-06): +# Monthly Notices of the Royal Astronomical Society 44, 4 (1884-02-08), 208 +# says that New York City Hall time was 3 minutes 58.4 seconds fast of +# Eastern time (i.e., -4:56:01.6) just before the 1883 switch. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule NYC 1920 only - Mar lastSun 2:00 1:00 D +Rule NYC 1920 only - Oct lastSun 2:00 0 S +Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D +Rule NYC 1921 1954 - Sep lastSun 2:00 0 S +Rule NYC 1955 1966 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] + #STDOFF -4:56:01.6 +Zone America/New_York -4:56:02 - LMT 1883 Nov 18 17:00u + -5:00 US E%sT 1920 + -5:00 NYC E%sT 1942 + -5:00 US E%sT 1946 + -5:00 NYC E%sT 1967 + -5:00 US E%sT + +# US central time, represented by Chicago + +# Alabama, Arkansas, Florida panhandle (Bay, Calhoun, Escambia, +# Gulf, Holmes, Jackson, Okaloosa, Santa Rosa, Walton, and +# Washington counties), Illinois, western Indiana +# (Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer, +# Vanderburgh, and Warrick counties), Iowa, most of Kansas, western +# Kentucky, Louisiana, Minnesota, Mississippi, Missouri, eastern +# Nebraska, eastern North Dakota, Oklahoma, eastern South Dakota, +# western Tennessee, most of Texas, Wisconsin + +# From Paul Eggert (2018-01-07): +# In 1869 the Chicago Astronomical Society contracted with the city to keep +# time. Though delayed by the Great Fire, by 1880 a wire ran from the +# Dearborn Observatory (on the University of Chicago campus) to City Hall, +# which then sent signals to police and fire stations. However, railroads got +# their time signals from the Allegheny Observatory, the Madison Observatory, +# the Ann Arbor Observatory, etc., so their clocks did not agree with each +# other or with the city's official time. The confusion took some years to +# clear up. See: +# Moser M. How Chicago gave America its time zones. Chicago. 2018-01-04. +# http://www.chicagomag.com/city-life/January-2018/How-Chicago-Gave-America-Its-Time-Zones/ + +# From Larry M. Smith (2006-04-26) re Wisconsin: +# https://docs.legis.wisconsin.gov/statutes/statutes/175.pdf +# is currently enforced at the 01:00 time of change. Because the local +# "bar time" in the state corresponds to 02:00, a number of citations +# are issued for the "sale of class 'B' alcohol after prohibited +# hours" within the deviated hour of this change every year.... +# +# From Douglas R. Bomberg (2007-03-12): +# Wisconsin has enacted (nearly eleventh-hour) legislation to get WI +# Statue 175 closer in synch with the US Congress' intent.... +# https://docs.legis.wisconsin.gov/2007/related/acts/3 + +# From an email administrator of the City of Fort Pierre, SD (2015-12-21): +# Fort Pierre is technically located in the Mountain time zone as is +# the rest of Stanley County. Most of Stanley County and Fort Pierre +# uses the Central time zone due to doing most of their business in +# Pierre so it simplifies schedules. I have lived in Stanley County +# all my life and it has been that way since I can remember. (43 years!) +# +# From Paul Eggert (2015-12-25): +# Assume this practice predates 1970, so Fort Pierre can use America/Chicago. + +# From Paul Eggert (2015-04-06): +# In 1950s Nashville a public clock had dueling faces, one for conservatives +# and the other for liberals; the two sides didn't agree about the time of day. +# I haven't found a photo of this clock, nor have I tracked down the TIME +# magazine report cited below, but here's the story as told by the late +# American journalist John Seigenthaler, who was there: +# +# "The two [newspaper] owners held strongly contrasting political and +# ideological views. Evans was a New South liberal, Stahlman an Old South +# conservative, and their two papers frequently clashed editorially, often on +# the same day.... In the 1950s as the state legislature was grappling with +# the question of whether to approve daylight saving time for the entire state, +# TIME magazine reported: +# +# "'The Nashville Banner and The Nashville Tennessean rarely agree on anything +# but the time of day - and last week they couldn't agree on that.' +# +# "It was all too true. The clock on the front of the building had two faces - +# The Tennessean side of the building facing west, the other, east. When it +# was high noon Banner time, it was 11 a.m. Tennessean time." +# +# Seigenthaler J. For 100 years, Tennessean had it covered. +# The Tennessean 2007-05-11, republished 2015-04-06. +# https://www.tennessean.com/story/insider/extras/2015/04/06/archives-seigenthaler-for-100-years-the-tennessean-had-it-covered/25348545/ + +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Chicago 1920 only - Jun 13 2:00 1:00 D +Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S +Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D +Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D +Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S +Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1920 + -6:00 Chicago C%sT 1936 Mar 1 2:00 + -5:00 - EST 1936 Nov 15 2:00 + -6:00 Chicago C%sT 1942 + -6:00 US C%sT 1946 + -6:00 Chicago C%sT 1967 + -6:00 US C%sT +# Oliver County, ND switched from mountain to central time on 1992-10-25. +Zone America/North_Dakota/Center -6:45:12 - LMT 1883 Nov 18 19:00u + -7:00 US M%sT 1992 Oct 25 2:00 + -6:00 US C%sT +# Morton County, ND, switched from mountain to central time on +# 2003-10-26, except for the area around Mandan which was already central time. +# See <http://dmses.dot.gov/docimages/p63/135818.pdf>. +# Officially this switch also included part of Sioux County, and +# Jones, Mellette, and Todd Counties in South Dakota; +# but in practice these other counties were already observing central time. +# See <http://www.epa.gov/fedrgstr/EPA-IMPACT/2003/October/Day-28/i27056.htm>. +Zone America/North_Dakota/New_Salem -6:45:39 - LMT 1883 Nov 18 19:00u + -7:00 US M%sT 2003 Oct 26 2:00 + -6:00 US C%sT + +# From Josh Findley (2011-01-21): +# ...it appears that Mercer County, North Dakota, changed from the +# mountain time zone to the central time zone at the last transition from +# daylight-saving to standard time (on Nov. 7, 2010): +# https://www.gpo.gov/fdsys/pkg/FR-2010-09-29/html/2010-24376.htm +# http://www.bismarcktribune.com/news/local/article_1eb1b588-c758-11df-b472-001cc4c03286.html + +# From Andy Lipscomb (2011-01-24): +# ...according to the Census Bureau, the largest city is Beulah (although +# it's commonly referred to as Beulah-Hazen, with Hazen being the next +# largest city in Mercer County). Google Maps places Beulah's city hall +# at 47° 15' 51" N, 101° 46' 40" W, which yields an offset of 6h47'07". + +Zone America/North_Dakota/Beulah -6:47:07 - LMT 1883 Nov 18 19:00u + -7:00 US M%sT 2010 Nov 7 2:00 + -6:00 US C%sT + +# US mountain time, represented by Denver +# +# Colorado, far western Kansas, Montana, western +# Nebraska, Nevada border (Jackpot, Owyhee, and Mountain City), +# New Mexico, southwestern North Dakota, +# western South Dakota, far western Texas (El Paso County, Hudspeth County, +# and Pine Springs and Nickel Creek in Culberson County), Utah, Wyoming +# +# From Paul Eggert (2018-10-25): +# On 1921-03-04 federal law placed all of Texas into the central time zone. +# However, El Paso ignored the law for decades and continued to observe +# mountain time, on the grounds that that's what they had always done +# and they weren't about to let the federal government tell them what to do. +# Eventually the federal government gave in and changed the law on +# 1970-04-10 to match what El Paso was actually doing. Although +# that's slightly after our 1970 cutoff, there is no need to create a +# separate zone for El Paso since they were ignoring the law anyway. See: +# Long T. El Pasoans were time rebels, fought to stay in Mountain zone. +# El Paso Times. 2018-10-24 06:40 -06. +# https://www.elpasotimes.com/story/news/local/el-paso/2018/10/24/el-pasoans-were-time-rebels-fought-stay-mountain-zone/1744509002/ +# +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D +Rule Denver 1920 only - Oct lastSun 2:00 0 S +Rule Denver 1921 only - May 22 2:00 0 S +Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D +Rule Denver 1965 1966 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Denver -6:59:56 - LMT 1883 Nov 18 19:00u + -7:00 US M%sT 1920 + -7:00 Denver M%sT 1942 + -7:00 US M%sT 1946 + -7:00 Denver M%sT 1967 + -7:00 US M%sT + +# US Pacific time, represented by Los Angeles +# +# California, northern Idaho (Benewah, Bonner, Boundary, Clearwater, +# Kootenai, Latah, Lewis, Nez Perce, and Shoshone counties, Idaho county +# north of the Salmon River, and the towns of Burgdorf and Warren), +# Nevada (except West Wendover), Oregon (except the northern ¾ of +# Malheur county), and Washington + +# From Paul Eggert (2016-08-20): +# In early February 1948, in response to California's electricity shortage, +# PG&E changed power frequency from 60 to 59.5 Hz during daylight hours, +# causing electric clocks to lose six minutes per day. (This did not change +# legal time, and is not part of the data here.) See: +# Ross SA. An energy crisis from the past: Northern California in 1948. +# Working Paper No. 8, Institute of Governmental Studies, UC Berkeley, +# 1973-11. https://escholarship.org/uc/item/8x22k30c +# +# In another measure to save electricity, DST was instituted from 1948-03-14 +# at 02:01 to 1949-01-16 at 02:00, with the governor having the option to move +# the fallback transition earlier. See pages 3-4 of: +# http://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1948/48Vol1_Chapters.pdf +# +# In response: +# +# Governor Warren received a torrent of objecting mail, and it is not too much +# to speculate that the objections to Daylight Saving Time were one important +# factor in the defeat of the Dewey-Warren Presidential ticket in California. +# -- Ross, p 25 +# +# On December 8 the governor exercised the option, setting the date to January 1 +# (LA Times 1948-12-09). The transition time was 02:00 (LA Times 1949-01-01). +# +# Despite the controversy, in 1949 California voters approved Proposition 12, +# which established DST from April's last Sunday at 01:00 until September's +# last Sunday at 02:00. This was amended by 1962's Proposition 6, which changed +# the fall-back date to October's last Sunday. See: +# https://repository.uchastings.edu/cgi/viewcontent.cgi?article=1501&context=ca_ballot_props +# https://repository.uchastings.edu/cgi/viewcontent.cgi?article=1636&context=ca_ballot_props +# +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule CA 1948 only - Mar 14 2:01 1:00 D +Rule CA 1949 only - Jan 1 2:00 0 S +Rule CA 1950 1966 - Apr lastSun 1:00 1:00 D +Rule CA 1950 1961 - Sep lastSun 2:00 0 S +Rule CA 1962 1966 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 20:00u + -8:00 US P%sT 1946 + -8:00 CA P%sT 1967 + -8:00 US P%sT + +# Alaska +# AK%sT is the modern abbreviation for -09 per USNO. +# +# From Paul Eggert (2017-06-15): +# Howse writes that Alaska switched from the Julian to the Gregorian calendar, +# and from east-of-GMT to west-of-GMT days, when the US bought it from Russia. +# On Friday, 1867-10-18 (Gregorian), at precisely 15:30 local time, the +# Russian forts and fleet at Sitka fired salutes to mark the ceremony of +# formal transfer. See the Sacramento Daily Union (1867-11-14), p 3, col 2. +# https://cdnc.ucr.edu/cgi-bin/cdnc?a=d&d=SDU18671114.2.12.1 +# Sitka workers did not change their calendars until Sunday, 1867-10-20, +# and so celebrated two Sundays that week. See: Ahllund T (tr Hallamaa P). +# From the memoirs of a Finnish workman. Alaska History. 2006 Fall;21(2):1-25. +# http://alaskahistoricalsociety.org/wp-content/uploads/2016/12/Ahllund-2006-Memoirs-of-a-Finnish-Workman.pdf +# Include only the time zone part of this transition, ignoring the switch +# from Julian to Gregorian, since we can't represent the Julian calendar. +# +# As far as we know, of the locations mentioned below only Sitka was +# permanently inhabited in 1867 by anyone using either calendar. +# (Yakutat was colonized by the Russians in 1799, but the settlement was +# destroyed in 1805 by a Yakutat-kon war party.) Many of Alaska's inhabitants +# were unaware of the US acquisition of Alaska, much less of any calendar or +# time change. However, the Russian-influenced part of Alaska did observe +# Russian time, and it is more accurate to model this than to ignore it. +# The database format requires an exact transition time; use the Russian +# salute as a somewhat-arbitrary time for the formal transfer of control for +# all of Alaska. Sitka's UTC offset is -9:01:13; adjust its 15:30 to the +# local times of other Alaskan locations so that they change simultaneously. + +# From Paul Eggert (2014-07-18): +# One opinion of the early 1980s turmoil in Alaska over time zones and +# daylight saving time appeared as graffiti on a Juneau airport wall: +# "Welcome to Juneau. Please turn your watch back to the 19th century." +# See: Turner W. Alaska's four time zones now two. NY Times 1983-11-01. +# http://www.nytimes.com/1983/11/01/us/alaska-s-four-time-zones-now-two.html +# +# Steve Ferguson (2011-01-31) referred to the following source: +# Norris F. Keeping time in Alaska: national directives, local response. +# Alaska History 2001;16(1-2). +# http://alaskahistoricalsociety.org/discover-alaska/glimpses-of-the-past/keeping-time-in-alaska/ + +# From Arthur David Olson (2011-02-01): +# Here's database-relevant material from the 2001 "Alaska History" article: +# +# On September 20 [1979]...DOT...officials decreed that on April 27, +# 1980, Juneau and other nearby communities would move to Yukon Time. +# Sitka, Petersburg, Wrangell, and Ketchikan, however, would remain on +# Pacific Time. +# +# ...on September 22, 1980, DOT Secretary Neil E. Goldschmidt rescinded the +# Department's September 1979 decision. Juneau and other communities in +# northern Southeast reverted to Pacific Time on October 26. +# +# On October 28 [1983]...the Metlakatla Indian Community Council voted +# unanimously to keep the reservation on Pacific Time. +# +# According to DOT official Joanne Petrie, Indian reservations are not +# bound to follow time zones imposed by neighboring jurisdictions. +# +# (The last is consistent with how the database now handles the Navajo +# Nation.) + +# From Arthur David Olson (2011-02-09): +# I just spoke by phone with a staff member at the Metlakatla Indian +# Community office (using contact information available at +# http://www.commerce.state.ak.us/dca/commdb/CIS.cfm?Comm_Boro_name=Metlakatla +# It's shortly after 1:00 here on the east coast of the United States; +# the staffer said it was shortly after 10:00 there. When I asked whether +# that meant they were on Pacific time, they said no - they were on their +# own time. I asked about daylight saving; they said it wasn't used. I +# did not inquire about practices in the past. + +# From Arthur David Olson (2011-08-17): +# For lack of better information, assume that Metlakatla's +# abandonment of use of daylight saving resulted from the 1983 vote. + +# From Steffen Thorsen (2015-11-09): +# It seems Metlakatla did go off PST on Sunday, November 1, changing +# their time to AKST and are going to follow Alaska's DST, switching +# between AKST and AKDT from now on.... +# https://www.krbd.org/2015/10/30/annette-island-times-they-are-a-changing/ + +# From Ryan Stanley (2018-11-06): +# The Metlakatla community in Alaska has decided not to change its +# clock back an hour starting on November 4th, 2018 (day before yesterday). +# They will be gmtoff=-28800 year-round. +# https://www.facebook.com/141055983004923/photos/pb.141055983004923.-2207520000.1541465673./569081370202380/ + +# From Paul Eggert (2018-12-16): +# In a 2018-12-11 special election, Metlakatla voted to go back to +# Alaska time (including daylight saving time) starting next year. +# https://www.krbd.org/2018/12/12/metlakatla-to-follow-alaska-standard-time-allow-liquor-sales/ +# +# From Ryan Stanley (2019-01-11): +# The community will be changing back on the 20th of this month... +# From Tim Parenti (2019-01-11): +# Per an announcement on the Metlakatla community's official Facebook page, the +# "fall back" will be on Sunday 2019-01-20 at 02:00: +# https://www.facebook.com/141055983004923/photos/607150969728753/ +# So they won't be waiting for Alaska to join them on 2019-03-10, but will +# rather change their clocks twice in seven weeks. + +# From Paul Eggert (2023-01-23): +# America/Adak is for the Aleutian Islands that are part of Alaska +# and are west of 169.5° W. + +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Juneau 15:02:19 - LMT 1867 Oct 19 15:33:32 + -8:57:41 - LMT 1900 Aug 20 12:00 + -8:00 - PST 1942 + -8:00 US P%sT 1946 + -8:00 - PST 1969 + -8:00 US P%sT 1980 Apr 27 2:00 + -9:00 US Y%sT 1980 Oct 26 2:00 + -8:00 US P%sT 1983 Oct 30 2:00 + -9:00 US Y%sT 1983 Nov 30 + -9:00 US AK%sT +Zone America/Sitka 14:58:47 - LMT 1867 Oct 19 15:30 + -9:01:13 - LMT 1900 Aug 20 12:00 + -8:00 - PST 1942 + -8:00 US P%sT 1946 + -8:00 - PST 1969 + -8:00 US P%sT 1983 Oct 30 2:00 + -9:00 US Y%sT 1983 Nov 30 + -9:00 US AK%sT +Zone America/Metlakatla 15:13:42 - LMT 1867 Oct 19 15:44:55 + -8:46:18 - LMT 1900 Aug 20 12:00 + -8:00 - PST 1942 + -8:00 US P%sT 1946 + -8:00 - PST 1969 + -8:00 US P%sT 1983 Oct 30 2:00 + -8:00 - PST 2015 Nov 1 2:00 + -9:00 US AK%sT 2018 Nov 4 2:00 + -8:00 - PST 2019 Jan 20 2:00 + -9:00 US AK%sT +Zone America/Yakutat 14:41:05 - LMT 1867 Oct 19 15:12:18 + -9:18:55 - LMT 1900 Aug 20 12:00 + -9:00 - YST 1942 + -9:00 US Y%sT 1946 + -9:00 - YST 1969 + -9:00 US Y%sT 1983 Nov 30 + -9:00 US AK%sT +Zone America/Anchorage 14:00:24 - LMT 1867 Oct 19 14:31:37 + -9:59:36 - LMT 1900 Aug 20 12:00 + -10:00 - AST 1942 + -10:00 US A%sT 1967 Apr + -10:00 - AHST 1969 + -10:00 US AH%sT 1983 Oct 30 2:00 + -9:00 US Y%sT 1983 Nov 30 + -9:00 US AK%sT +Zone America/Nome 12:58:22 - LMT 1867 Oct 19 13:29:35 + -11:01:38 - LMT 1900 Aug 20 12:00 + -11:00 - NST 1942 + -11:00 US N%sT 1946 + -11:00 - NST 1967 Apr + -11:00 - BST 1969 + -11:00 US B%sT 1983 Oct 30 2:00 + -9:00 US Y%sT 1983 Nov 30 + -9:00 US AK%sT +Zone America/Adak 12:13:22 - LMT 1867 Oct 19 12:44:35 + -11:46:38 - LMT 1900 Aug 20 12:00 + -11:00 - NST 1942 + -11:00 US N%sT 1946 + -11:00 - NST 1967 Apr + -11:00 - BST 1969 + -11:00 US B%sT 1983 Oct 30 2:00 + -10:00 US AH%sT 1983 Nov 30 + -10:00 US H%sT +# The following switches don't make our 1970 cutoff. +# +# Kiska observed Tokyo date and time during Japanese occupation from +# 1942-06-06 to 1943-07-29, and similarly for Attu from 1942-06-07 to +# 1943-05-29 (all dates American). Both islands are now uninhabited. +# +# Shanks writes that part of southwest Alaska (e.g. Aniak) +# switched from -11:00 to -10:00 on 1968-09-22 at 02:00, +# and another part (e.g. Akiak) made the same switch five weeks later. +# +# From David Flater (2004-11-09): +# In e-mail, 2004-11-02, Ray Hudson, historian/liaison to the Unalaska +# Historic Preservation Commission, provided this information, which +# suggests that Unalaska deviated from statutory time from early 1967 +# possibly until 1983: +# +# Minutes of the Unalaska City Council Meeting, January 10, 1967: +# "Except for St. Paul and Akutan, Unalaska is the only important +# location not on Alaska Standard Time. The following resolution was +# made by William Robinson and seconded by Henry Swanson: Be it +# resolved that the City of Unalaska hereby goes to Alaska Standard +# Time as of midnight Friday, January 13, 1967 (1 A.M. Saturday, +# January 14, Alaska Standard Time.) This resolution was passed with +# three votes for and one against." + +# Hawaii + +# From Arthur David Olson (2010-12-09): +# "Hawaiian Time" by Robert C. Schmitt and Doak C. Cox appears on pages 207-225 +# of volume 26 of The Hawaiian Journal of History (1992). As of 2010-12-09, +# the article is available at +# https://evols.library.manoa.hawaii.edu/bitstream/10524/239/2/JL26215.pdf +# and indicates that standard time was adopted effective noon, January +# 13, 1896 (page 218), that in "1933, the Legislature decreed daylight +# saving for the period between the last Sunday of each April and the +# last Sunday of each September, but less than a month later repealed the +# act," (page 220), that year-round daylight saving time was in effect +# from 1942-02-09 to 1945-09-30 (page 221, with no time of day given for +# when clocks changed) and that clocks were changed by 30 minutes +# effective the second Sunday of June, 1947 (page 219, with no time of +# day given for when clocks changed). A footnote for the 1933 changes +# cites Session Laws of Hawaii 1933, "Act. 90 (approved 26 Apr. 1933) +# and Act 163 (approved 21 May 1933)." + +# From Arthur David Olson (2011-01-19): +# The following is from "Laws of the Territory of Hawaii Passed by the +# Seventeenth Legislature: Regular Session 1933," available (as of +# 2011-01-19) at American University's Pence Law Library. Page 85: "Act +# 90...At 2 o'clock ante meridian of the last Sunday in April of each +# year, the standard time of this Territory shall be advanced one +# hour...This Act shall take effect upon its approval. Approved this 26th +# day of April, A. D. 1933. LAWRENCE M JUDD, Governor of the Territory of +# Hawaii." Page 172: "Act 163...Act 90 of the Session Laws of 1933 is +# hereby repealed...This Act shall take effect upon its approval, upon +# which date the standard time of this Territory shall be restored to +# that existing immediately prior to the taking effect of said Act 90. +# Approved this 21st day of May, A. D. 1933. LAWRENCE M. JUDD, Governor +# of the Territory of Hawaii." +# +# Note that 1933-05-21 was a Sunday. +# We're left to guess the time of day when Act 163 was approved; guess noon. + +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone Pacific/Honolulu -10:31:26 - LMT 1896 Jan 13 12:00 + -10:30 - HST 1933 Apr 30 2:00 + -10:30 1:00 HDT 1933 May 21 12:00 + -10:30 US H%sT 1947 Jun 8 2:00 + -10:00 - HST + +# Now we turn to US areas that have diverged from the consensus since 1970. + +# Arizona mostly uses MST. + +# From Paul Eggert (2002-10-20): +# +# The information in the rest of this paragraph is derived from the +# Daylight Saving Time web page +# <http://www.dlapr.lib.az.us/links/daylight.htm> (2002-01-23) +# maintained by the Arizona State Library, Archives and Public Records. +# Between 1944-01-01 and 1944-04-01 the State of Arizona used standard +# time, but by federal law railroads, airlines, bus lines, military +# personnel, and some engaged in interstate commerce continued to +# observe war (i.e., daylight saving) time. The 1944-03-17 Phoenix +# Gazette says that was the date the law changed, and that 04-01 was +# the date the state's clocks would change. In 1945 the State of +# Arizona used standard time all year, again with exceptions only as +# mandated by federal law. Arizona observed DST in 1967, but Arizona +# Laws 1968, ch. 183 (effective 1968-03-21) repealed DST. +# +# Shanks says the 1944 experiment came to an end on 1944-03-17. +# Go with the Arizona State Library instead. + +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 19:00u + -7:00 US M%sT 1944 Jan 1 0:01 + -7:00 - MST 1944 Apr 1 0:01 + -7:00 US M%sT 1944 Oct 1 0:01 + -7:00 - MST 1967 + -7:00 US M%sT 1968 Mar 21 + -7:00 - MST + +# From Arthur David Olson (1988-02-13): +# A writer from the Inter Tribal Council of Arizona, Inc., +# notes in private correspondence dated 1987-12-28 that "Presently, only the +# Navajo Nation participates in the Daylight Saving Time policy, due to its +# large size and location in three states." (The "only" means that other +# tribal nations don't use DST.) +# +# From Paul Eggert (2013-08-26): +# See America/Denver for a zone appropriate for the Navajo Nation. + +# Southern Idaho (Ada, Adams, Bannock, Bear Lake, Bingham, Blaine, +# Boise, Bonneville, Butte, Camas, Canyon, Caribou, Cassia, Clark, +# Custer, Elmore, Franklin, Fremont, Gem, Gooding, Jefferson, Jerome, +# Lemhi, Lincoln, Madison, Minidoka, Oneida, Owyhee, Payette, Power, +# Teton, Twin Falls, Valley, Washington counties, and the southern +# quarter of Idaho county) and eastern Oregon (most of Malheur County) +# switched four weeks late in 1974. +# +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Boise -7:44:49 - LMT 1883 Nov 18 20:00u + -8:00 US P%sT 1923 May 13 2:00 + -7:00 US M%sT 1974 + -7:00 - MST 1974 Feb 3 2:00 + -7:00 US M%sT + +# Indiana +# +# For a map of Indiana's time zone regions, see: +# https://en.wikipedia.org/wiki/Time_in_Indiana +# +# From Paul Eggert (2018-11-30): +# A brief but entertaining history of time in Indiana describes a 1949 debate +# in the Indiana House where city legislators (who favored "fast time") +# tussled with farm legislators (who didn't) over a bill to outlaw DST: +# "Lacking enough votes, the city faction tries to filibuster until time runs +# out on the session at midnight, but rural champion Rep. Herbert Copeland, +# R-Madison, leans over the gallery railing and forces the official clock +# back to 9 p.m., breaking it in the process. The clock sticks on 9 as the +# debate rages on into the night. The filibuster finally dies out and the +# bill passes, while outside the chamber, clocks read 3:30 a.m. In the end, +# it doesn't matter which side won. The law has no enforcement powers and +# is simply ignored by fast-time communities." +# How Indiana went from 'God's time' to split zones and daylight-saving. +# Indianapolis Star. 2018-11-27 14:58 -05. +# https://www.indystar.com/story/news/politics/2018/11/27/indianapolis-indiana-time-zone-history-central-eastern-daylight-savings-time/2126300002/ +# +# From Paul Eggert (2007-08-17): +# Since 1970, most of Indiana has been like America/Indiana/Indianapolis, +# with the following exceptions: +# +# - Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer, +# Vanderburgh, and Warrick counties have been like America/Chicago. +# +# - Dearborn and Ohio counties have been like America/New_York. +# +# - Clark, Floyd, and Harrison counties have been like +# America/Kentucky/Louisville. +# +# - Crawford, Daviess, Dubois, Knox, Martin, Perry, Pike, Pulaski, Starke, +# and Switzerland counties have their own time zone histories as noted below. +# +# Shanks partitioned Indiana into 345 regions, each with its own time history, +# and wrote "Even newspaper reports present contradictory information." +# Those Hoosiers! Such a flighty and changeable people! +# Fortunately, most of the complexity occurred before our cutoff date of 1970. +# +# Other than Indianapolis, the Indiana place names are so nondescript +# that they would be ambiguous if we left them at the 'America' level. +# So we reluctantly put them all in a subdirectory 'America/Indiana'. + +# From Paul Eggert (2014-06-26): +# https://www.federalregister.gov/articles/2006/01/20/06-563/standard-time-zone-boundary-in-the-state-of-indiana +# says "DOT is relocating the time zone boundary in Indiana to move Starke, +# Pulaski, Knox, Daviess, Martin, Pike, Dubois, and Perry Counties from the +# Eastern Time Zone to the Central Time Zone.... The effective date of +# this rule is 2 a.m. EST Sunday, April 2, 2006, which is the +# changeover date from standard time to Daylight Saving Time." +# Strictly speaking, this meant the affected counties changed their +# clocks twice that night, but this obviously was in error. The intent +# was that 01:59:59 EST be followed by 02:00:00 CDT. + +# From Gwillim Law (2007-02-10): +# The Associated Press has been reporting that Pulaski County, Indiana is +# going to switch from Central to Eastern Time on March 11, 2007.... +# http://www.indystar.com/apps/pbcs.dll/article?AID=/20070207/LOCAL190108/702070524/0/LOCAL + +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D +Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S +Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Indiana/Indianapolis -5:44:38 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1920 + -6:00 Indianapolis C%sT 1942 + -6:00 US C%sT 1946 + -6:00 Indianapolis C%sT 1955 Apr 24 2:00 + -5:00 - EST 1957 Sep 29 2:00 + -6:00 - CST 1958 Apr 27 2:00 + -5:00 - EST 1969 + -5:00 US E%sT 1971 + -5:00 - EST 2006 + -5:00 US E%sT +# +# Eastern Crawford County, Indiana, left its clocks alone in 1974, +# as well as from 1976 through 2005. +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D +Rule Marengo 1951 only - Sep lastSun 2:00 0 S +Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D +Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1951 + -6:00 Marengo C%sT 1961 Apr 30 2:00 + -5:00 - EST 1969 + -5:00 US E%sT 1974 Jan 6 2:00 + -6:00 1:00 CDT 1974 Oct 27 2:00 + -5:00 US E%sT 1976 + -5:00 - EST 2006 + -5:00 US E%sT +# +# Daviess, Dubois, Knox, and Martin Counties, Indiana, +# switched from eastern to central time in April 2006, then switched back +# in November 2007. +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Vincennes 1946 only - Apr lastSun 2:00 1:00 D +Rule Vincennes 1946 only - Sep lastSun 2:00 0 S +Rule Vincennes 1953 1954 - Apr lastSun 2:00 1:00 D +Rule Vincennes 1953 1959 - Sep lastSun 2:00 0 S +Rule Vincennes 1955 only - May 1 0:00 1:00 D +Rule Vincennes 1956 1963 - Apr lastSun 2:00 1:00 D +Rule Vincennes 1960 only - Oct lastSun 2:00 0 S +Rule Vincennes 1961 only - Sep lastSun 2:00 0 S +Rule Vincennes 1962 1963 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Indiana/Vincennes -5:50:07 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1946 + -6:00 Vincennes C%sT 1964 Apr 26 2:00 + -5:00 - EST 1969 + -5:00 US E%sT 1971 + -5:00 - EST 2006 Apr 2 2:00 + -6:00 US C%sT 2007 Nov 4 2:00 + -5:00 US E%sT +# +# Perry County, Indiana, switched from eastern to central time in April 2006. +# From Alois Treindl (2019-07-09): +# The Indianapolis News, Friday 27 October 1967 states that Perry County +# returned to CST. It went again to EST on 27 April 1969, as documented by the +# Indianapolis star of Saturday 26 April. +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Perry 1955 only - May 1 0:00 1:00 D +Rule Perry 1955 1960 - Sep lastSun 2:00 0 S +Rule Perry 1956 1963 - Apr lastSun 2:00 1:00 D +Rule Perry 1961 1963 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Indiana/Tell_City -5:47:03 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1946 + -6:00 Perry C%sT 1964 Apr 26 2:00 + -5:00 - EST 1967 Oct 29 2:00 + -6:00 US C%sT 1969 Apr 27 2:00 + -5:00 US E%sT 1971 + -5:00 - EST 2006 Apr 2 2:00 + -6:00 US C%sT +# +# Pike County, Indiana moved from central to eastern time in 1977, +# then switched back in 2006, then switched back again in 2007. +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Pike 1955 only - May 1 0:00 1:00 D +Rule Pike 1955 1960 - Sep lastSun 2:00 0 S +Rule Pike 1956 1964 - Apr lastSun 2:00 1:00 D +Rule Pike 1961 1964 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Indiana/Petersburg -5:49:07 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1955 + -6:00 Pike C%sT 1965 Apr 25 2:00 + -5:00 - EST 1966 Oct 30 2:00 + -6:00 US C%sT 1977 Oct 30 2:00 + -5:00 - EST 2006 Apr 2 2:00 + -6:00 US C%sT 2007 Nov 4 2:00 + -5:00 US E%sT +# +# Starke County, Indiana moved from central to eastern time in 1991, +# then switched back in 2006. +# From Arthur David Olson (1991-10-28): +# An article on page A3 of the Sunday, 1991-10-27 Washington Post +# notes that Starke County switched from Central time to Eastern time as of +# 1991-10-27. +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D +Rule Starke 1947 1954 - Sep lastSun 2:00 0 S +Rule Starke 1955 1956 - Oct lastSun 2:00 0 S +Rule Starke 1957 1958 - Sep lastSun 2:00 0 S +Rule Starke 1959 1961 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1947 + -6:00 Starke C%sT 1962 Apr 29 2:00 + -5:00 - EST 1963 Oct 27 2:00 + -6:00 US C%sT 1991 Oct 27 2:00 + -5:00 - EST 2006 Apr 2 2:00 + -6:00 US C%sT +# +# Pulaski County, Indiana, switched from eastern to central time in +# April 2006 and then switched back in March 2007. +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Pulaski 1946 1960 - Apr lastSun 2:00 1:00 D +Rule Pulaski 1946 1954 - Sep lastSun 2:00 0 S +Rule Pulaski 1955 1956 - Oct lastSun 2:00 0 S +Rule Pulaski 1957 1960 - Sep lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Indiana/Winamac -5:46:25 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1946 + -6:00 Pulaski C%sT 1961 Apr 30 2:00 + -5:00 - EST 1969 + -5:00 US E%sT 1971 + -5:00 - EST 2006 Apr 2 2:00 + -6:00 US C%sT 2007 Mar 11 2:00 + -5:00 US E%sT +# +# Switzerland County, Indiana, did not observe DST from 1973 through 2005. +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1954 Apr 25 2:00 + -5:00 - EST 1969 + -5:00 US E%sT 1973 + -5:00 - EST 2006 + -5:00 US E%sT + +# From Paul Eggert (2018-03-20): +# The Louisville & Nashville Railroad's 1883-11-18 change occurred at +# 10:00 old local time; train were supposed to come to a standstill +# for precisely 18 minutes. See Bartky Fig. 1 (page 50). It is not +# clear how this matched civil time in Louisville, so for now continue +# to assume Louisville switched at noon new local time, like New York. +# +# From Michael Deckers (2019-08-06): +# From the contemporary source given by Alois Treindl, +# the switch in Louisville on 1946-04-28 was on 00:01 +# From Paul Eggert (2019-08-26): +# That source was the Louisville Courier-Journal, 1946-04-27, p 4. +# Shanks gives 02:00 for all 20th-century transition times in Louisville. +# Evidently this is wrong for spring 1946. Although also likely wrong +# for other dates, we have no data. +# +# Part of Kentucky left its clocks alone in 1974. +# This also includes Clark, Floyd, and Harrison counties in Indiana. +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Louisville 1921 only - May 1 2:00 1:00 D +Rule Louisville 1921 only - Sep 1 2:00 0 S +Rule Louisville 1941 only - Apr lastSun 2:00 1:00 D +Rule Louisville 1941 only - Sep lastSun 2:00 0 S +Rule Louisville 1946 only - Apr lastSun 0:01 1:00 D +Rule Louisville 1946 only - Jun 2 2:00 0 S +Rule Louisville 1950 1961 - Apr lastSun 2:00 1:00 D +Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S +Rule Louisville 1956 1961 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Kentucky/Louisville -5:43:02 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1921 + -6:00 Louisville C%sT 1942 + -6:00 US C%sT 1946 + -6:00 Louisville C%sT 1961 Jul 23 2:00 + -5:00 - EST 1968 + -5:00 US E%sT 1974 Jan 6 2:00 + -6:00 1:00 CDT 1974 Oct 27 2:00 + -5:00 US E%sT +# +# Wayne County, Kentucky +# +# From Lake Cumberland LIFE +# http://www.lake-cumberland.com/life/archive/news990129time.shtml +# (1999-01-29) via WKYM-101.7: +# Clinton County has joined Wayne County in asking the DoT to change from +# the Central to the Eastern time zone.... The Wayne County government made +# the same request in December. And while Russell County officials have not +# taken action, the majority of respondents to a poll conducted there in +# August indicated they would like to change to "fast time" also. +# The three Lake Cumberland counties are the farthest east of any U.S. +# location in the Central time zone. +# +# From Rich Wales (2000-08-29): +# After prolonged debate, and despite continuing deep differences of opinion, +# Wayne County (central Kentucky) is switching from Central (-0600) to Eastern +# (-0500) time. They won't "fall back" this year. See Sara Shipley, +# The difference an hour makes, Nando Times (2000-08-29 15:33 -0400). +# +# From Paul Eggert (2001-07-16): +# The final rule was published in the +# Federal Register 65, 160 (2000-08-17), pp 50154-50158. +# https://www.gpo.gov/fdsys/pkg/FR-2000-08-17/html/00-20854.htm +# +Zone America/Kentucky/Monticello -5:39:24 - LMT 1883 Nov 18 18:00u + -6:00 US C%sT 1946 + -6:00 - CST 1968 + -6:00 US C%sT 2000 Oct 29 2:00 + -5:00 US E%sT + + +# From Rives McDow (2000-08-30): +# Here ... are all the changes in the US since 1985. +# Kearny County, KS (put all of county on central; +# previously split between MST and CST) ... 1990-10 +# Starke County, IN (from CST to EST) ... 1991-10 +# Oliver County, ND (from MST to CST) ... 1992-10 +# West Wendover, NV (from PST TO MST) ... 1999-10 +# Wayne County, KY (from CST to EST) ... 2000-10 +# +# From Paul Eggert (2001-07-17): +# We don't know where the line used to be within Kearny County, KS, +# so omit that change for now. +# See America/Indiana/Knox for the Starke County, IN change. +# See America/North_Dakota/Center for the Oliver County, ND change. +# West Wendover, NV officially switched from Pacific to mountain time on +# 1999-10-31. See the +# Federal Register 64, 203 (1999-10-21), pp 56705-56707. +# https://www.gpo.gov/fdsys/pkg/FR-1999-10-21/html/99-27240.htm +# However, the Federal Register says that West Wendover already operated +# on mountain time, and the rule merely made this official; +# hence a separate tz entry is not needed. + +# Michigan +# +# From Bob Devine (1988-01-28): +# Michigan didn't observe DST from 1968 to 1973. +# +# From Paul Eggert (1999-03-31): +# Shanks writes that Michigan started using standard time on 1885-09-18, +# but Howse writes (pp 124-125, referring to Popular Astronomy, 1901-01) +# that Detroit kept +# +# local time until 1900 when the City Council decreed that clocks should +# be put back twenty-eight minutes to Central Standard Time. Half the +# city obeyed, half refused. After considerable debate, the decision +# was rescinded and the city reverted to Sun time. A derisive offer to +# erect a sundial in front of the city hall was referred to the +# Committee on Sewers. Then, in 1905, Central time was adopted +# by city vote. +# +# This story is too entertaining to be false, so go with Howse over Shanks. +# +# From Paul Eggert (2001-03-06): +# Garland (1927) writes "Cleveland and Detroit advanced their clocks +# one hour in 1914." This change is not in Shanks. We have no more +# info, so omit this for now. +# +# From Paul Eggert (2019-07-06): +# Due to a complicated set of legal maneuvers, in 1967 Michigan did +# not start daylight saving time when the rest of the US did. +# Instead, it began DST on Jun 14 at 00:01. This was big news: +# the Detroit Free Press reported it at the top of Page 1 on +# 1967-06-14, in an article "State Adjusting to Switch to Fast Time" +# by Gary Blonston, above an article about Thurgood Marshall's +# confirmation to the US Supreme Court. Although Shanks says Detroit +# observed DST until 1967-10-29 00:01, that time of day seems to be +# incorrect, as the Free Press later said DST ended in Michigan at the +# same time as the rest of the US. Also, although Shanks reports no DST in +# Detroit in 1968, it did observe DST that year; in the November 1968 +# election Michigan voters narrowly repealed DST, effective 1969. +# +# Most of Michigan observed DST from 1973 on, but was a bit late in 1975. +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D +Rule Detroit 1948 only - Sep lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Detroit -5:32:11 - LMT 1905 + -6:00 - CST 1915 May 15 2:00 + -5:00 - EST 1942 + -5:00 US E%sT 1946 + -5:00 Detroit E%sT 1967 Jun 14 0:01 + -5:00 US E%sT 1969 + -5:00 - EST 1973 + -5:00 US E%sT 1975 + -5:00 - EST 1975 Apr 27 2:00 + -5:00 US E%sT +# +# Dickinson, Gogebic, Iron, and Menominee Counties, Michigan, +# switched from EST to CST/CDT in 1973. +# Rule NAME FROM TO - IN ON AT SAVE LETTER +Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D +Rule Menominee 1946 only - Sep lastSun 2:00 0 S +Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D +Rule Menominee 1966 only - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00 + -6:00 US C%sT 1946 + -6:00 Menominee C%sT 1969 Apr 27 2:00 + -5:00 - EST 1973 Apr 29 2:00 + -6:00 US C%sT + +# Navassa +# administered by the US Fish and Wildlife Service +# claimed by US under the provisions of the 1856 Guano Islands Act +# also claimed by Haiti +# occupied 1857/1900 by the Navassa Phosphate Co +# US lighthouse 1917/1996-09 +# currently uninhabited +# see Mark Fineman, "An Isle Rich in Guano and Discord", +# _Los Angeles Times_ (1998-11-10), A1, A10; it cites +# Jimmy Skaggs, _The Great Guano Rush_ (1994). + +################################################################################ + + +# From Paul Eggert (2017-02-10): +# +# Unless otherwise specified, the source for data through 1990 is: +# Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition), +# San Diego: ACS Publications, Inc. (2003). +# Unfortunately this book contains many errors and cites no sources. +# +# Many years ago Gwillim Law wrote that a good source +# for time zone data was the International Air Transport +# Association's Standard Schedules Information Manual (IATA SSIM), +# published semiannually. Law sent in several helpful summaries +# of the IATA's data after 1990. Except where otherwise noted, +# IATA SSIM is the source for entries after 1990. +# +# Other sources occasionally used include: +# +# Milne J. Civil time. Geogr J. 1899 Feb;13(2):173-94 +# <https://www.jstor.org/stable/1774359>. +# +# Pearce C. The Great Daylight Saving Time Controversy. +# Australian Ebook Publisher. 2017. ISBN 978-1-925516-96-8. +# +# Edward W. Whitman, World Time Differences, +# Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), +# which I found in the UCLA library. +# +# William Willett, The Waste of Daylight, 19th edition +# <http://cs.ucla.edu/~eggert/The-Waste-of-Daylight-19th.pdf> +# [PDF] (1914-03) +# +# For the 1911/1912 establishment of standard time in French possessions, see: +# Société Française de Physique, Recueil de constantes physiques (1913), +# page 752, 18b. +# +# See the 'europe' file for Greenland. + +# Canada + +# From Alain LaBonté (1994-11-14): +# I post here the time zone abbreviations standardized in Canada +# for both English and French in the CAN/CSA-Z234.4-89 standard.... +# +# UTC Standard time Daylight saving time +# offset French English French English +# -2:30 - - HAT NDT +# -3 - - HAA ADT +# -3:30 HNT NST - - +# -4 HNA AST HAE EDT +# -5 HNE EST HAC CDT +# -6 HNC CST HAR MDT +# -7 HNR MST HAP PDT +# -8 HNP PST HAY YDT +# -9 HNY YST - - +# +# HN: Heure Normale ST: Standard Time +# HA: Heure Avancée DT: Daylight saving Time +# +# A: de l'Atlantique Atlantic +# C: du Centre Central +# E: de l'Est Eastern +# M: Mountain +# N: Newfoundland +# P: du Pacifique Pacific +# R: des Rocheuses +# T: de Terre-Neuve +# Y: du Yukon Yukon +# +# From Paul Eggert (1994-11-22): +# Alas, this sort of thing must be handled by localization software. + +# Unless otherwise specified, the data entries for Canada are all from Shanks +# & Pottenger. + +# From Chris Walton (2006-04-01, 2006-04-25, 2006-06-26, 2007-01-31, +# 2007-03-01): +# The British Columbia government announced yesterday that it will +# adjust daylight savings next year to align with changes in the +# U.S. and the rest of Canada.... +# https://archive.news.gov.bc.ca/releases/news_releases_2005-2009/2006AG0014-000330.htm +# ... +# Nova Scotia +# Daylight saving time will be extended by four weeks starting in 2007.... +# https://www.novascotia.ca/just/regulations/rg2/2006/ma1206.pdf +# +# [For New Brunswick] the new legislation dictates that the time change is to +# be done at 02:00 instead of 00:01. +# https://www.gnb.ca/0062/acts/BBA-2006/Chap-19.pdf +# ... +# Manitoba has traditionally changed the clock every fall at 03:00. +# As of 2006, the transition is to take place one hour earlier at 02:00. +# https://web2.gov.mb.ca/laws/statutes/ccsm/o030e.php +# ... +# [Alberta, Ontario, Quebec] will follow US rules. +# http://www.qp.gov.ab.ca/documents/spring/CH03_06.CFM +# http://www.e-laws.gov.on.ca/DBLaws/Source/Regs/English/2006/R06111_e.htm +# http://www2.publicationsduquebec.gouv.qc.ca/dynamicSearch/telecharge.php?type=5&file=2006C39A.PDF +# ... +# P.E.I. will follow US rules.... +# http://www.assembly.pe.ca/bills/pdf_chapter/62/3/chapter-41.pdf +# ... +# Province of Newfoundland and Labrador.... +# http://www.hoa.gov.nl.ca/hoa/bills/Bill0634.htm +# ... +# Yukon +# https://www.gov.yk.ca/legislation/regs/oic2006_127.pdf +# ... +# N.W.T. will follow US rules. Whoever maintains the government web site +# does not seem to believe in bookmarks. To see the news release, click the +# following link and search for "Daylight Savings Time Change". Press the +# "Daylight Savings Time Change" link; it will fire off a popup using +# JavaScript. +# http://www.exec.gov.nt.ca/currentnews/currentPR.asp?mode=archive +# ... +# Nunavut +# An amendment to the Interpretation Act was registered on February 19/2007.... +# http://action.attavik.ca/home/justice-gn/attach/2007/gaz02part2.pdf + +# From Paul Eggert (2014-10-18): +# H. David Matthews and Mary Vincent's map +# "It's about TIME", _Canadian Geographic_ (September-October 1998) +# https://web.archive.org/web/19990827055050/https://canadiangeographic.ca/SO98/geomap.htm +# contains detailed boundaries for regions observing nonstandard +# time and daylight saving time arrangements in Canada circa 1998. +# +# National Research Council Canada maintains info about time zones and DST. +# https://www.nrc-cnrc.gc.ca/eng/services/time/time_zones.html +# https://www.nrc-cnrc.gc.ca/eng/services/time/faq/index.html#Q5 +# Its unofficial information is often taken from Matthews and Vincent. + +# From Paul Eggert (2006-06-27): +# For now, assume all of DST-observing Canada will fall into line with the +# new US DST rules, + +# From Chris Walton (2011-12-01) +# In the first of Tammy Hardwick's articles +# http://www.ilovecreston.com/?p=articles&t=spec&ar=260 +# she quotes the Friday November 1/1918 edition of the Creston Review. +# The quote includes these two statements: +# 'Sunday the CPR went back to the old system of time...' +# '... The daylight saving scheme was dropped all over Canada at the same time,' +# These statements refer to a transition from daylight time to standard time +# that occurred nationally on Sunday October 27/1918. This transition was +# also documented in the Saturday October 26/1918 edition of the Toronto Star. + +# In light of that evidence, we alter the date from the earlier believed +# Oct 31, to Oct 27, 1918 (and Sunday is a more likely transition day +# than Thursday) in all Canadian rulesets. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Canada 1918 only - Apr 14 2:00 1:00 D +Rule Canada 1918 only - Oct 27 2:00 0 S +Rule Canada 1942 only - Feb 9 2:00 1:00 W # War +Rule Canada 1945 only - Aug 14 23:00u 1:00 P # Peace +Rule Canada 1945 only - Sep 30 2:00 0 S +Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D +Rule Canada 1974 2006 - Oct lastSun 2:00 0 S +Rule Canada 1987 2006 - Apr Sun>=1 2:00 1:00 D +Rule Canada 2007 max - Mar Sun>=8 2:00 1:00 D +Rule Canada 2007 max - Nov Sun>=1 2:00 0 S + + +# Newfoundland and Labrador + +# From Paul Eggert (2017-10-14): +# Legally Labrador should observe Newfoundland time; see: +# McLeod J. Labrador time - legal or not? St. John's Telegram, 2017-10-07 +# http://www.thetelegram.com/news/local/labrador-time--legal-or-not-154860/ +# Matthews and Vincent (1998) write that the only part of Labrador +# that follows the rules is the southeast corner, including Port Hope +# Simpson and Mary's Harbour, but excluding, say, Black Tickle. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule StJohns 1917 only - Apr 8 2:00 1:00 D +Rule StJohns 1917 only - Sep 17 2:00 0 S +# Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks & Pottenger. +Rule StJohns 1919 only - May 5 23:00 1:00 D +Rule StJohns 1919 only - Aug 12 23:00 0 S +# For 1931-1935 Whitman gives Apr same date; go with Shanks & Pottenger. +Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D +Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S +# For 1936-1941 Whitman gives May Sun>=8 and Oct Sun>=1; go with Shanks & +# Pottenger. +Rule StJohns 1936 1941 - May Mon>=9 0:00 1:00 D +Rule StJohns 1936 1941 - Oct Mon>=2 0:00 0 S +# Whitman gives the following transitions: +# 1942 03-01/12-31, 1943 05-30/09-05, 1944 07-10/09-02, 1945 01-01/10-07 +# but go with Shanks & Pottenger and assume they used Canadian rules. +# For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives +# Apr 30 - Sep 24; go with Shanks & Pottenger. +Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D +Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S +Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D +Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S +Rule StJohns 1960 1986 - Oct lastSun 2:00 0 S +# From Paul Eggert (2000-10-02): +# INMS (2000-09-12) says that, since 1988 at least, Newfoundland switches +# at 00:01 local time. For now, assume it started in 1987. + +# From Michael Pelley (2011-09-12): +# We received today, Monday, September 12, 2011, notification that the +# changes to the Newfoundland Standard Time Act have been proclaimed. +# The change in the Act stipulates that the change from Daylight Savings +# Time to Standard Time and from Standard Time to Daylight Savings Time +# now occurs at 2:00AM. +# ... +# http://www.assembly.nl.ca/legislation/sr/annualstatutes/2011/1106.chp.htm +# ... +# MICHAEL PELLEY | Manager of Enterprise Architecture - Solution Delivery +# Office of the Chief Information Officer +# Executive Council +# Government of Newfoundland & Labrador + +Rule StJohns 1987 only - Apr Sun>=1 0:01 1:00 D +Rule StJohns 1987 2006 - Oct lastSun 0:01 0 S +Rule StJohns 1988 only - Apr Sun>=1 0:01 2:00 DD +Rule StJohns 1989 2006 - Apr Sun>=1 0:01 1:00 D +Rule StJohns 2007 2011 - Mar Sun>=8 0:01 1:00 D +Rule StJohns 2007 2010 - Nov Sun>=1 0:01 0 S +# +# St John's has an apostrophe, but POSIX file names can't have apostrophes. +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/St_Johns -3:30:52 - LMT 1884 + -3:30:52 StJohns N%sT 1918 + -3:30:52 Canada N%sT 1919 + -3:30:52 StJohns N%sT 1935 Mar 30 + -3:30 StJohns N%sT 1942 May 11 + -3:30 Canada N%sT 1946 + -3:30 StJohns N%sT 2011 Nov + -3:30 Canada N%sT + +# most of east Labrador + +# The name 'Happy Valley-Goose Bay' is too long; use 'Goose Bay'. +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Goose_Bay -4:01:40 - LMT 1884 # Happy Valley-Goose Bay + -3:30:52 - NST 1918 + -3:30:52 Canada N%sT 1919 + -3:30:52 - NST 1935 Mar 30 + -3:30 - NST 1936 + -3:30 StJohns N%sT 1942 May 11 + -3:30 Canada N%sT 1946 + -3:30 StJohns N%sT 1966 Mar 15 2:00 + -4:00 StJohns A%sT 2011 Nov + -4:00 Canada A%sT + + +# west Labrador, Nova Scotia, Prince Edward I, +# Îles-de-la-Madeleine, Listuguj reserve + +# From Brian Inglis (2015-07-20): +# From the historical weather station records available at: +# https://weatherspark.com/history/28351/1971/Sydney-Nova-Scotia-Canada +# Sydney shares the same time history as Glace Bay, so was +# likely to be the same across the island.... +# Sydney, as the capital and most populous location, or Cape Breton, would +# have been better names for the zone had we known this in 1996. + +# From Paul Eggert (2015-07-20): +# Shanks & Pottenger write that since 1970 most of this region has been like +# Halifax. Many locales did not observe peacetime DST until 1972; +# the Cape Breton area, represented by Glace Bay, is the largest we know of +# (Glace Bay was perhaps not the best name choice but no point changing now). +# Shanks & Pottenger also write that Liverpool, NS was the only town +# in Canada to observe DST in 1971 but not 1970; for now we'll assume +# this is a typo. + +# From Jeffery Nichols (2020-01-09): +# America/Halifax ... also applies to Îles-de-la-Madeleine and the Listuguj +# reserve in Quebec. Officially, this came into effect on January 1, 2007 +# (Legal Time Act, CQLR c T-5.1), but the legislative debates surrounding that +# bill say that it is "accommodating the customs and practices" of those +# regions, which suggests that they have always been in-line with Halifax. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Halifax 1916 only - Apr 1 0:00 1:00 D +Rule Halifax 1916 only - Oct 1 0:00 0 S +Rule Halifax 1920 only - May 9 0:00 1:00 D +Rule Halifax 1920 only - Aug 29 0:00 0 S +Rule Halifax 1921 only - May 6 0:00 1:00 D +Rule Halifax 1921 1922 - Sep 5 0:00 0 S +Rule Halifax 1922 only - Apr 30 0:00 1:00 D +Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D +Rule Halifax 1923 only - Sep 4 0:00 0 S +Rule Halifax 1924 only - Sep 15 0:00 0 S +Rule Halifax 1925 only - Sep 28 0:00 0 S +Rule Halifax 1926 only - May 16 0:00 1:00 D +Rule Halifax 1926 only - Sep 13 0:00 0 S +Rule Halifax 1927 only - May 1 0:00 1:00 D +Rule Halifax 1927 only - Sep 26 0:00 0 S +Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D +Rule Halifax 1928 only - Sep 9 0:00 0 S +Rule Halifax 1929 only - Sep 3 0:00 0 S +Rule Halifax 1930 only - Sep 15 0:00 0 S +Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S +Rule Halifax 1932 only - May 1 0:00 1:00 D +Rule Halifax 1933 only - Apr 30 0:00 1:00 D +Rule Halifax 1933 only - Oct 2 0:00 0 S +Rule Halifax 1934 only - May 20 0:00 1:00 D +Rule Halifax 1934 only - Sep 16 0:00 0 S +Rule Halifax 1935 only - Jun 2 0:00 1:00 D +Rule Halifax 1935 only - Sep 30 0:00 0 S +Rule Halifax 1936 only - Jun 1 0:00 1:00 D +Rule Halifax 1936 only - Sep 14 0:00 0 S +Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D +Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S +Rule Halifax 1939 only - May 28 0:00 1:00 D +Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D +Rule Halifax 1946 1949 - Apr lastSun 2:00 1:00 D +Rule Halifax 1946 1949 - Sep lastSun 2:00 0 S +Rule Halifax 1951 1954 - Apr lastSun 2:00 1:00 D +Rule Halifax 1951 1954 - Sep lastSun 2:00 0 S +Rule Halifax 1956 1959 - Apr lastSun 2:00 1:00 D +Rule Halifax 1956 1959 - Sep lastSun 2:00 0 S +Rule Halifax 1962 1973 - Apr lastSun 2:00 1:00 D +Rule Halifax 1962 1973 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Halifax -4:14:24 - LMT 1902 Jun 15 + -4:00 Halifax A%sT 1918 + -4:00 Canada A%sT 1919 + -4:00 Halifax A%sT 1942 Feb 9 2:00s + -4:00 Canada A%sT 1946 + -4:00 Halifax A%sT 1974 + -4:00 Canada A%sT +Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15 + -4:00 Canada A%sT 1953 + -4:00 Halifax A%sT 1954 + -4:00 - AST 1972 + -4:00 Halifax A%sT 1974 + -4:00 Canada A%sT + +# New Brunswick + +# From Paul Eggert (2007-01-31): +# The Time Definition Act <http://www.gnb.ca/0062/PDF-acts/t-06.pdf> +# says they changed at 00:01 through 2006, and +# <http://www.canlii.org/nb/laws/sta/t-6/20030127/whole.html> makes it +# clear that this was the case since at least 1993. +# For now, assume it started in 1993. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Moncton 1933 1935 - Jun Sun>=8 1:00 1:00 D +Rule Moncton 1933 1935 - Sep Sun>=8 1:00 0 S +Rule Moncton 1936 1938 - Jun Sun>=1 1:00 1:00 D +Rule Moncton 1936 1938 - Sep Sun>=1 1:00 0 S +Rule Moncton 1939 only - May 27 1:00 1:00 D +Rule Moncton 1939 1941 - Sep Sat>=21 1:00 0 S +Rule Moncton 1940 only - May 19 1:00 1:00 D +Rule Moncton 1941 only - May 4 1:00 1:00 D +Rule Moncton 1946 1972 - Apr lastSun 2:00 1:00 D +Rule Moncton 1946 1956 - Sep lastSun 2:00 0 S +Rule Moncton 1957 1972 - Oct lastSun 2:00 0 S +Rule Moncton 1993 2006 - Apr Sun>=1 0:01 1:00 D +Rule Moncton 1993 2006 - Oct lastSun 0:01 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Moncton -4:19:08 - LMT 1883 Dec 9 + -5:00 - EST 1902 Jun 15 + -4:00 Canada A%sT 1933 + -4:00 Moncton A%sT 1942 + -4:00 Canada A%sT 1946 + -4:00 Moncton A%sT 1973 + -4:00 Canada A%sT 1993 + -4:00 Moncton A%sT 2007 + -4:00 Canada A%sT + +# Quebec + +# From Paul Eggert (2020-01-10): +# See America/Toronto for most of Quebec, including Montreal. +# See America/Halifax for the Îles de la Madeleine and the Listuguj reserve. +# See America/Puerto_Rico for east of Natashquan. + +# Ontario + +# From Mark Brader (2003-07-26): +# [According to the Toronto Star] Orillia, Ontario, adopted DST +# effective Saturday, 1912-06-22, 22:00; the article mentions that +# Port Arthur (now part of Thunder Bay, Ontario) as well as Moose Jaw +# have already done so. In Orillia DST was to run until Saturday, +# 1912-08-31 (no time mentioned), but it was met with considerable +# hostility from certain segments of the public, and was revoked after +# only two weeks - I copied it as Saturday, 1912-07-07, 22:00, but +# presumably that should be -07-06. (1912-06-19, -07-12; also letters +# earlier in June). +# +# Kenora, Ontario, was to abandon DST on 1914-06-01 (-05-21). +# +# From Paul Eggert (2017-07-08): +# For more on Orillia, see: Daubs K. Bold attempt at daylight saving +# time became a comic failure in Orillia. Toronto Star 2017-07-08. +# https://www.thestar.com/news/insight/2017/07/08/bold-attempt-at-daylight-saving-time-became-a-comic-failure-in-orillia.html + +# From Mark Brader (2010-03-06): +# +# In the (Toronto) Globe and Mail for Saturday, 1955-09-24, in the bottom +# right corner of page 1, it says that Toronto will return to standard +# time at 2 am Sunday morning (which agrees with the database), and that: +# +# The one-hour setback will go into effect throughout most of Ontario, +# except in areas like Windsor which remains on standard time all year. +# +# ... I don't know if Windsor began observing DST when Detroit did, +# or in 1974, or on some other date. +# +# By the way, the article continues by noting that: +# +# Some cities in the United States have pushed the deadline back +# three weeks and will change over from daylight saving in October. + +# From Chris Walton (2024-01-09): +# The [Toronto] changes in 1947, 1948, and 1949 took place at 2:00 a.m. local +# time instead of midnight.... Toronto Daily Star - ... +# April 2, 1947 - Page 39 ... April 7, 1948 - Page 13 ... +# April 2, 1949 - Page 1 ... April 7, 1949 - Page 24 ... +# November 25, 1949 - Page 52 ... April 21, 1950 - Page 14 ... +# September 19, 1950 - Page 46 ... September 20, 1950 - Page 3 ... +# November 24, 1950 - Page 21 + +# From Arthur David Olson (2010-07-17): +# +# "Standard Time and Time Zones in Canada" appeared in +# The Journal of The Royal Astronomical Society of Canada, +# volume 26, number 2 (February 1932) and, as of 2010-07-17, +# was available at +# http://adsabs.harvard.edu/full/1932JRASC..26...49S +# +# It includes the text below (starting on page 57): +# +# A list of the places in Canada using daylight saving time would +# require yearly revision. From information kindly furnished by +# the provincial governments and by the postmasters in many cities +# and towns, it is found that the following places used daylight sav- +# ing in 1930. The information for the province of Quebec is definite, +# for the other provinces only approximate: +# +# Province Daylight saving time used +# Prince Edward Island Not used. +# Nova Scotia In Halifax only. +# New Brunswick In St. John only. +# Quebec In the following places: +# Montreal Lachine +# Quebec Mont-Royal +# Lévis Iberville +# St. Lambert Cap de la Madelèine +# Verdun Loretteville +# Westmount Richmond +# Outremont St. Jérôme +# Longueuil Greenfield Park +# Arvida Waterloo +# Chambly-Canton Beaulieu +# Melbourne La Tuque +# St. Théophile Buckingham +# Ontario Used generally in the cities and towns along +# the southerly part of the province. Not +# used in the northwesterly part. +# Manitoba Not used. +# Saskatchewan In Regina only. +# Alberta Not used. +# British Columbia Not used. +# +# With some exceptions, the use of daylight saving may be said to be limited +# to those cities and towns lying between Quebec city and Windsor, Ont. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Toronto 1919 only - Mar 30 23:30 1:00 D +Rule Toronto 1919 only - Oct 26 0:00 0 S +Rule Toronto 1920 only - May 2 2:00 1:00 D +Rule Toronto 1920 only - Sep 26 0:00 0 S +Rule Toronto 1921 only - May 15 2:00 1:00 D +Rule Toronto 1921 only - Sep 15 2:00 0 S +Rule Toronto 1922 1923 - May Sun>=8 2:00 1:00 D +# Shanks & Pottenger say 1923-09-19; assume it's a typo and that "-16" +# was meant. +Rule Toronto 1922 1926 - Sep Sun>=15 2:00 0 S +Rule Toronto 1924 1927 - May Sun>=1 2:00 1:00 D +Rule Toronto 1927 1937 - Sep Sun>=25 2:00 0 S +Rule Toronto 1928 1937 - Apr Sun>=25 2:00 1:00 D +Rule Toronto 1938 1940 - Apr lastSun 2:00 1:00 D +Rule Toronto 1938 1939 - Sep lastSun 2:00 0 S +Rule Toronto 1945 1948 - Sep lastSun 2:00 0 S +Rule Toronto 1946 1973 - Apr lastSun 2:00 1:00 D +Rule Toronto 1949 1950 - Nov lastSun 2:00 0 S +Rule Toronto 1951 1956 - Sep lastSun 2:00 0 S +# Shanks & Pottenger say Toronto ended DST a week early in 1971, +# namely on 1971-10-24, but Mark Brader wrote (2003-05-31) that this +# is wrong, and that he had confirmed it by checking the 1971-10-30 +# Toronto Star, which said that DST was ending 1971-10-31 as usual. +Rule Toronto 1957 1973 - Oct lastSun 2:00 0 S + +# The Bahamas match Toronto since 1970. + +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Toronto -5:17:32 - LMT 1895 + -5:00 Canada E%sT 1919 + -5:00 Toronto E%sT 1942 Feb 9 2:00s + -5:00 Canada E%sT 1946 + -5:00 Toronto E%sT 1974 + -5:00 Canada E%sT +# For Atikokan see America/Panama. + + +# Manitoba + +# From Rob Douglas (2006-04-06): +# the old Manitoba Time Act - as amended by Bill 2, assented to +# March 27, 1987 ... said ... +# "between two o'clock Central Standard Time in the morning of +# the first Sunday of April of each year and two o'clock Central +# Standard Time in the morning of the last Sunday of October next +# following, one hour in advance of Central Standard Time."... +# I believe that the English legislation [of the old time act] had +# been assented to (March 22, 1967).... +# Also, as far as I can tell, there was no order-in-council varying +# the time of Daylight Saving Time for 2005 and so the provisions of +# the 1987 version would apply - the changeover was at 2:00 Central +# Standard Time (i.e. not until 3:00 Central Daylight Time). + +# From Paul Eggert (2006-04-10): +# Shanks & Pottenger say Manitoba switched at 02:00 (not 02:00s) +# starting 1966. Since 02:00s is clearly correct for 1967 on, assume +# it was also 02:00s in 1966. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Winn 1916 only - Apr 23 0:00 1:00 D +Rule Winn 1916 only - Sep 17 0:00 0 S +Rule Winn 1918 only - Apr 14 2:00 1:00 D +Rule Winn 1918 only - Oct 27 2:00 0 S +Rule Winn 1937 only - May 16 2:00 1:00 D +Rule Winn 1937 only - Sep 26 2:00 0 S +Rule Winn 1942 only - Feb 9 2:00 1:00 W # War +Rule Winn 1945 only - Aug 14 23:00u 1:00 P # Peace +Rule Winn 1945 only - Sep lastSun 2:00 0 S +Rule Winn 1946 only - May 12 2:00 1:00 D +Rule Winn 1946 only - Oct 13 2:00 0 S +Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D +Rule Winn 1947 1949 - Sep lastSun 2:00 0 S +Rule Winn 1950 only - May 1 2:00 1:00 D +Rule Winn 1950 only - Sep 30 2:00 0 S +Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D +Rule Winn 1951 1958 - Sep lastSun 2:00 0 S +Rule Winn 1959 only - Oct lastSun 2:00 0 S +Rule Winn 1960 only - Sep lastSun 2:00 0 S +Rule Winn 1963 only - Apr lastSun 2:00 1:00 D +Rule Winn 1963 only - Sep 22 2:00 0 S +Rule Winn 1966 1986 - Apr lastSun 2:00s 1:00 D +Rule Winn 1966 2005 - Oct lastSun 2:00s 0 S +Rule Winn 1987 2005 - Apr Sun>=1 2:00s 1:00 D +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16 + -6:00 Winn C%sT 2006 + -6:00 Canada C%sT + + +# Saskatchewan + +# From Mark Brader (2003-07-26): +# The first actual adoption of DST in Canada was at the municipal +# level. As the [Toronto] Star put it (1912-06-07), "While people +# elsewhere have long been talking of legislation to save daylight, +# the city of Moose Jaw [Saskatchewan] has acted on its own hook." +# DST in Moose Jaw began on Saturday, 1912-06-01 (no time mentioned: +# presumably late evening, as below), and would run until "the end of +# the summer". The discrepancy between municipal time and railroad +# time was noted. + +# From Paul Eggert (2003-07-27): +# Willett (1914-03) notes that DST "has been in operation ... in the +# City of Moose Jaw, Saskatchewan, for one year." + +# From Paul Eggert (2019-07-25): +# Pearce's book says Regina observed DST in 1914-1917. No dates and times, +# unfortunately. It also says that in 1914 Saskatoon observed DST +# from 1 June to 6 July, and that DST was also tried out in Davidson, +# Melfort, and Prince Albert. + +# From Paul Eggert (2006-03-22): +# Shanks & Pottenger say that since 1970 this region has mostly been as Regina. +# Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972. +# Other western towns (e.g. Lloydminster) are like Edmonton. +# Matthews and Vincent (1998) write that Denare Beach and Creighton +# are like Winnipeg, in violation of Saskatchewan law. + +# From W. Jones (1992-11-06): +# The. . .below is based on information I got from our law library, the +# provincial archives, and the provincial Community Services department. +# A precise history would require digging through newspaper archives, and +# since you didn't say what you wanted, I didn't bother. +# +# Saskatchewan is split by a time zone meridian (105W) and over the years +# the boundary became pretty ragged as communities near it reevaluated +# their affiliations in one direction or the other. In 1965 a provincial +# referendum favoured legislating common time practices. +# +# On 15 April 1966 the Time Act (c. T-14, Revised Statutes of +# Saskatchewan 1978) was proclaimed, and established that the eastern +# part of Saskatchewan would use CST year round, that districts in +# northwest Saskatchewan would by default follow CST but could opt to +# follow Mountain Time rules (thus 1 hour difference in the winter and +# zero in the summer), and that districts in southwest Saskatchewan would +# by default follow MT but could opt to follow CST. +# +# It took a few years for the dust to settle (I know one story of a town +# on one time zone having its school in another, such that a mom had to +# serve her family lunch in two shifts), but presently it seems that only +# a few towns on the border with Alberta (e.g. Lloydminster) follow MT +# rules any more; all other districts appear to have used CST year round +# since sometime in the 1960s. + +# From Chris Walton (2006-06-26): +# The Saskatchewan time act which was last updated in 1996 is about 30 pages +# long and rather painful to read. +# http://www.qp.gov.sk.ca/documents/English/Statutes/Statutes/T14.pdf + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Regina 1918 only - Apr 14 2:00 1:00 D +Rule Regina 1918 only - Oct 27 2:00 0 S +Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D +Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S +Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D +Rule Regina 1937 only - Oct Sun>=8 0:00 0 S +Rule Regina 1938 only - Oct Sun>=1 0:00 0 S +Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S +Rule Regina 1942 only - Feb 9 2:00 1:00 W # War +Rule Regina 1945 only - Aug 14 23:00u 1:00 P # Peace +Rule Regina 1945 only - Sep lastSun 2:00 0 S +Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D +Rule Regina 1946 only - Oct Sun>=8 2:00 0 S +Rule Regina 1947 1957 - Apr lastSun 2:00 1:00 D +Rule Regina 1947 1957 - Sep lastSun 2:00 0 S +Rule Regina 1959 only - Apr lastSun 2:00 1:00 D +Rule Regina 1959 only - Oct lastSun 2:00 0 S +# +Rule Swift 1957 only - Apr lastSun 2:00 1:00 D +Rule Swift 1957 only - Oct lastSun 2:00 0 S +Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D +Rule Swift 1959 only - Oct lastSun 2:00 0 S +Rule Swift 1960 1961 - Sep lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Regina -6:58:36 - LMT 1905 Sep + -7:00 Regina M%sT 1960 Apr lastSun 2:00 + -6:00 - CST +Zone America/Swift_Current -7:11:20 - LMT 1905 Sep + -7:00 Canada M%sT 1946 Apr lastSun 2:00 + -7:00 Regina M%sT 1950 + -7:00 Swift M%sT 1972 Apr lastSun 2:00 + -6:00 - CST + + +# Alberta + +# From Alois Treindl (2019-07-19): +# There was no DST in Alberta in 1967... Calgary Herald, 29 April 1967. +# 1969, no DST, from Edmonton Journal 18 April 1969 +# +# From Paul Eggert (2019-07-25): +# Pearce's book says that Alberta's 1948 Daylight Saving Act required +# Mountain Standard Time without DST, and that "anyone who broke that law +# could be fined up to $25 and costs". There seems to be no record of +# anybody paying the fine. The law was not changed until an August 1971 +# plebiscite reinstituted DST in 1972. This story is also mentioned in: +# Boyer JP. Forcing Choice: The Risky Reward of Referendums. Dundum. 2017. +# ISBN 978-1459739123. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D +Rule Edm 1918 only - Oct 27 2:00 0 S +Rule Edm 1919 only - May 27 2:00 0 S +Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D +Rule Edm 1920 only - Oct lastSun 2:00 0 S +Rule Edm 1921 1923 - Sep lastSun 2:00 0 S +Rule Edm 1942 only - Feb 9 2:00 1:00 W # War +Rule Edm 1945 only - Aug 14 23:00u 1:00 P # Peace +Rule Edm 1945 only - Sep lastSun 2:00 0 S +Rule Edm 1947 only - Apr lastSun 2:00 1:00 D +Rule Edm 1947 only - Sep lastSun 2:00 0 S +Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D +Rule Edm 1972 2006 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Edmonton -7:33:52 - LMT 1906 Sep + -7:00 Edm M%sT 1987 + -7:00 Canada M%sT + + +# British Columbia + +# From Paul Eggert (2006-03-22): +# Shanks & Pottenger write that since 1970 most of this region has +# been like Vancouver. +# Dawson Creek uses MST. Much of east BC is like Edmonton. + +# From Matt Johnson (2015-09-21): +# Fort Nelson, BC, Canada will cancel DST this year. So while previously they +# were aligned with America/Vancouver, they're now aligned with +# America/Dawson_Creek. +# http://www.northernrockies.ca/EN/meta/news/archives/2015/northern-rockies-time-change.html +# +# From Tim Parenti (2015-09-23): +# This requires a new zone for the Northern Rockies Regional Municipality, +# America/Fort_Nelson. The resolution of 2014-12-08 was reached following a +# 2014-11-15 poll with nearly 75% support. Effectively, the municipality has +# been on MST (-0700) like Dawson Creek since it advanced its clocks on +# 2015-03-08. +# +# From Paul Eggert (2019-07-25): +# Shanks says Fort Nelson did not observe DST in 1946, unlike Vancouver. +# Alois Treindl confirmed this on 07-22, citing the 1946-04-27 Vancouver Daily +# Province. He also cited the 1946-09-28 Victoria Daily Times, which said +# that Vancouver, Victoria, etc. "change at midnight Saturday"; for now, +# guess they meant 02:00 Sunday since 02:00 was common practice in Vancouver. +# +# Early Vancouver, Volume Four, by Major J.S. Matthews, V.D., 2011 edition +# says that a 1922 plebiscite adopted DST, but a 1923 plebiscite rejected it. +# http://former.vancouver.ca/ctyclerk/archives/digitized/EarlyVan/SearchEarlyVan/Vol4pdf/MatthewsEarlyVancouverVol4_DaylightSavings.pdf +# A catalog entry for a newspaper clipping seems to indicate that Vancouver +# observed DST in 1941 from 07-07 through 09-27; see +# https://searcharchives.vancouver.ca/daylight-saving-1918-starts-again-july-7-1941-start-d-s-sept-27-end-of-d-s-1941 +# We have no further details, so omit them for now. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Vanc 1918 only - Apr 14 2:00 1:00 D +Rule Vanc 1918 only - Oct 27 2:00 0 S +Rule Vanc 1942 only - Feb 9 2:00 1:00 W # War +Rule Vanc 1945 only - Aug 14 23:00u 1:00 P # Peace +Rule Vanc 1945 only - Sep 30 2:00 0 S +Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D +Rule Vanc 1946 only - Sep 29 2:00 0 S +Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S +Rule Vanc 1962 2006 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Vancouver -8:12:28 - LMT 1884 + -8:00 Vanc P%sT 1987 + -8:00 Canada P%sT +Zone America/Dawson_Creek -8:00:56 - LMT 1884 + -8:00 Canada P%sT 1947 + -8:00 Vanc P%sT 1972 Aug 30 2:00 + -7:00 - MST +Zone America/Fort_Nelson -8:10:47 - LMT 1884 + -8:00 Vanc P%sT 1946 + -8:00 - PST 1947 + -8:00 Vanc P%sT 1987 + -8:00 Canada P%sT 2015 Mar 8 2:00 + -7:00 - MST +# For Creston see America/Phoenix. + +# Northwest Territories, Nunavut, Yukon + +# From Chris Walton (2022-11-06): +# Whitehorse Star - Thursday April 22, 1965 - page 1 +# title: DST Starts Monday ... +# https://www.newspapers.com/image/578587481/ +# The title of this first article is wrong and/or misleading. +# Also, the start time shown in the article is vague; it simply says "after +# midnight" when it probably should have stated 2:00a.m.... +# +# Whitehorse Star - Monday October 25, 1965 - page 15 ... +# https://www.newspapers.com/image/578589147/ +# The 1965 Yukon Council minutes can be found here: +# http://assets.yukonarchives.ca/PER_YG_06_1965_C20_S02_v1.pdf +# ... I do not currently believe that NWT touched any of its clocks in 1965.... +# +# Whitehorse Star - Thursday Feb 24,1966 - page 2 +# title: It's Time for YDT ... +# https://www.newspapers.com/image/578575979/ ... +# America/Whitehorse as a permanent change from UTC-9(YST) to +# UTC-8(PST) at 00:00 on Sunday February 27, 1966.... +# +# Whitehorse Star - Friday April 28,1972 - page 6 +# title: Daylight Saving Time for N.W.T.... +# https://www.newspapers.com/image/578701610/ ... +# Nunavut and NWT zones ... DST starting in 1972.... Start and End ... +# should be the same as the rest of Canada +# +# +# From Paul Eggert (2022-11-06): +# For now, assume Yukon's 1965-04-22 spring forward was 00:00 -> 02:00, as this +# seems likely than 02:00 -> 04:00 and matches "after midnight". + +# From Paul Eggert (2006-03-22): +# Dawson switched to PST in 1973. Inuvik switched to MST in 1979. +# Mathew Englander (1996-10-07) gives the following refs: +# * 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68, +# c. 7 defines Yukon standard time as UTC-9.... +# see Interpretation Act, R.S.C. 1985, c. I-21, s. 35(1). +# [https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-i-21/latest/rsc-1985-c-i-21.html] +# * C.O. 1973/214 switched Yukon to PST on 1973-10-28 00:00. +# * O.I.C. 1980/02 established DST. +# * O.I.C. 1987/056 changed DST to Apr firstSun 2:00 to Oct lastSun 2:00. + +# From Brian Inglis (2015-04-14): +# +# I tried to trace the history of Yukon time and found the following +# regulations, giving the reference title and URL if found, regulation name, +# and relevant quote if available. Each regulation specifically revokes its +# predecessor. The final reference is to the current Interpretation Act +# authorizing and resulting from these regulatory changes. +# +# Only recent regulations were retrievable via Yukon government site search or +# index, and only some via Canadian legal sources. Other sources used include +# articles titled "Standard Time and Time Zones in Canada" from JRASC via ADS +# Abstracts, cited by ADO for 1932 ..., and updated versions from 1958 and +# 1970 quoted below; each article includes current extracts from provincial +# and territorial ST and DST regulations at the end, summaries and details of +# standard times and daylight saving time at many locations across Canada, +# with time zone maps, tables and calculations for Canadian Sunrise, Sunset, +# and LMST; they also cover many countries and global locations, with a chart +# and table showing current Universal Time offsets, and may be useful as +# another source of information for 1970 and earlier. +# +# * Standard Time and Time Zones in Canada; Smith, C.C.; JRASC, Vol. 26, +# pp.49-77; February 1932; SAO/NASA Astrophysics Data System (ADS) +# http://adsabs.harvard.edu/abs/1932JRASC..26...49S from p.75: +# Yukon Interpretation Ordinance +# Yukon standard time is the local mean time at the one hundred and +# thirty-fifth meridian. +# +# * Standard Time and Time Zones in Canada; Smith, C.C.; Thomson, Malcolm M.; +# JRASC, Vol. 52, pp.193-223; October 1958; SAO/NASA Astrophysics Data System +# (ADS) http://adsabs.harvard.edu/abs/1958JRASC..52..193S from pp.220-1: +# Yukon Interpretation Ordinance, 1955, Chap. 16. +# +# (1) Subject to this section, standard time shall be reckoned as nine +# hours behind Greenwich Time and called Yukon Standard Time. +# +# (2) Notwithstanding subsection (1), the Commissioner may make regulations +# varying the manner of reckoning standard time. +# +# * Yukon Territory Commissioner's Order 1966-20 Interpretation Ordinance +# [no online source found] +# +# * Standard Time and Time Zones in Canada; Thomson, Malcolm M.; JRASC, +# Vol. 64, pp.129-162; June 1970; SAO/NASA Astrophysics Data System (ADS) +# http://adsabs.harvard.edu/abs/1970JRASC..64..129T from p.156: Yukon +# Territory Commissioner's Order 1967-59 Interpretation Ordinance ... +# +# 1. Commissioner's Order 1966-20 dated at Whitehorse in the Yukon +# Territory on 27th January, 1966, is hereby revoked. +# +# 2. Yukon (East) Standard Time as defined by section 36 of the +# Interpretation Ordinance from and after mid-night on the 28th day of May, +# 1967 shall be reckoned in the same manner as Pacific Standard Time, that +# is to say, eight hours behind Greenwich Time in the area of the Yukon +# Territory lying east of the 138th degree longitude west. +# +# 3. In the remainder of the Territory, lying west of the 138th degree +# longitude west, Yukon (West) Standard Time shall be reckoned as nine +# hours behind Greenwich Time. +# +# * Yukon Standard Time defined as Pacific Standard Time, YCO 1973/214 +# https://www.canlii.org/en/yk/laws/regu/yco-1973-214/latest/yco-1973-214.html +# C.O. 1973/214 INTERPRETATION ACT ... +# +# 1. Effective October 28, 1973 Commissioner's Order 1967/59 is hereby +# revoked. +# +# 2. Yukon Standard Time as defined by section 36 of the Interpretation +# Act from and after midnight on the twenty-eighth day of October, 1973 +# shall be reckoned in the same manner as Pacific Standard Time, that is +# to say eight hours behind Greenwich Time. +# +# * O.I.C. 1980/02 INTERPRETATION ACT +# https://mm.icann.org/pipermail/tz/attachments/20201125/d5adc93b/CAYTOIC1980-02DST1980-01-04-0001.pdf +# +# * Yukon Daylight Saving Time, YOIC 1987/56 +# https://www.canlii.org/en/yk/laws/regu/yoic-1987-56/latest/yoic-1987-56.html +# O.I.C. 1987/056 INTERPRETATION ACT ... +# +# In every year between +# (a) two o'clock in the morning in the first Sunday in April, and +# (b) two o'clock in the morning in the last Sunday in October, +# Standard Time shall be reckoned as seven hours behind Greenwich Time and +# called Yukon Daylight Saving Time. +# ... +# Dated ... 9th day of March, A.D., 1987. +# +# * Yukon Daylight Saving Time 2006, YOIC 2006/127 +# https://www.canlii.org/en/yk/laws/regu/yoic-2006-127/latest/yoic-2006-127.html +# O.I.C. 2006/127 INTERPRETATION ACT ... +# +# 1. In Yukon each year the time for general purposes shall be 7 hours +# behind Greenwich mean time during the period commencing at two o'clock +# in the forenoon on the second Sunday of March and ending at two o'clock +# in the forenoon on the first Sunday of November and shall be called +# Yukon Daylight Saving Time. +# +# 2. Order-in-Council 1987/56 is revoked. +# +# 3. This order comes into force January 1, 2007. +# +# * Interpretation Act, RSY 2002, c 125 +# https://www.canlii.org/en/yk/laws/stat/rsy-2002-c-125/latest/rsy-2002-c-125.html + +# From Chris Walton (2022-11-06): +# The 5th edition of the Atlas of Canada contains a time zone map that +# shows both legislated and observed time zone boundaries. +# All communities on Baffin Island are shown to be observing Eastern time. +# The date on the map is 1984. +# https://ftp.maps.canada.ca/pub/nrcan_rncan/raster/atlas_5_ed/eng/other/referencemaps/mcr4056.pdf + +# From Rives McDow (1999-09-04): +# Nunavut ... moved ... to incorporate the whole territory into one time zone. +# Nunavut moves to single time zone Oct. 31 +# http://www.nunatsiaq.com/nunavut/nvt90903_13.html + +# From Paul Eggert (1999-09-20): +# Basic Facts: The New Territory +# http://www.nunavut.com/basicfacts/english/basicfacts_1territory.html +# (1999) reports that ... Coral Harbour does not observe DST. + +# From Paul Eggert (2000-10-02): +# Matthews and Vincent (1998) say the following, but we lack histories +# for these potential new Zones. +# +# The Canadian Forces station at Alert uses Eastern Time while the +# handful of residents at the Eureka weather station [in the Central +# zone] skip daylight savings. Baffin Island, which is crossed by the +# Central, Eastern and Atlantic Time zones only uses Eastern Time. +# Gjoa Haven, Taloyoak and Pelly Bay all use Mountain instead of +# Central Time and Southampton Island [in the Central zone] is not +# required to use daylight savings. + +# From <http://www.nunatsiaqonline.ca/archives/nunavut001130/nvt21110_02.html> +# Nunavut now has two time zones (2000-11-10): +# The Nunavut government would allow its employees in Kugluktuk and +# Cambridge Bay to operate on central time year-round, putting them +# one hour behind the rest of Nunavut for six months during the winter. +# At the end of October the two communities had rebelled against +# Nunavut's unified time zone, refusing to shift to eastern time with +# the rest of the territory for the winter. Cambridge Bay remained on +# central time, while Kugluktuk, even farther west, reverted to +# mountain time, which they had used before the advent of Nunavut's +# unified time zone in 1999. +# +# From Rives McDow (2001-01-20), quoting the Nunavut government: +# The preceding decision came into effect at midnight, Saturday Nov 4, 2000. + +# From Paul Eggert (2000-12-04): +# Let's just keep track of the official times for now. + +# From Rives McDow (2001-03-07): +# The premier of Nunavut has issued a ministerial statement advising +# that effective 2001-04-01, the territory of Nunavut will revert +# back to three time zones (mountain, central, and eastern). Of the +# cities in Nunavut, Coral Harbor is the only one that I know of that +# has said it will not observe dst, staying on EST year round. I'm +# checking for more info, and will get back to you if I come up with +# more. +# [Also see <http://www.nunatsiaq.com/nunavut/nvt10309_06.html> (2001-03-09).] + +# From Gwillim Law (2005-05-21): +# According to ... +# http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp +# (from a 1998 Canadian Geographic article), the de facto and de jure time +# for Southampton Island (at the north end of Hudson Bay) is UTC-5 all year +# round. Using Google, it's easy to find other websites that confirm this. +# I wasn't able to find how far back this time regimen goes, but since it +# predates the creation of Nunavut, it probably goes back many years.... +# The Inuktitut name of Coral Harbour is Sallit, but it's rarely used. +# +# From Paul Eggert (2014-10-17): +# For lack of better information, assume that Southampton Island observed +# daylight saving only during wartime. Gwillim Law's email also +# mentioned maps now maintained by National Research Council Canada; +# see above for an up-to-date link. + +# From Chris Walton (2007-03-01): +# ... the community of Resolute (located on Cornwallis Island in +# Nunavut) moved from Central Time to Eastern Time last November. +# Basically the community did not change its clocks at the end of +# daylight saving.... +# http://www.nnsl.com/frames/newspapers/2006-11/nov13_06none.html + +# From Chris Walton (2011-03-21): +# Back in 2007 I initiated the creation of a new "zone file" for Resolute +# Bay. Resolute Bay is a small community located about 900km north of +# the Arctic Circle. The zone file was required because Resolute Bay had +# decided to use UTC-5 instead of UTC-6 for the winter of 2006-2007. +# +# According to new information which I received last week, Resolute Bay +# went back to using UTC-6 in the winter of 2007-2008... +# +# On March 11/2007 most of Canada went onto daylight saving. On March +# 14/2007 I phoned the Resolute Bay hamlet office to do a "time check." I +# talked to somebody that was both knowledgeable and helpful. I was able +# to confirm that Resolute Bay was still operating on UTC-5. It was +# explained to me that Resolute Bay had been on the Eastern Time zone +# (EST) in the winter, and was now back on the Central Time zone (CDT). +# i.e. the time zone had changed twice in the last year but the clocks +# had not moved. The residents had to know which time zone they were in +# so they could follow the correct TV schedule... +# +# On Nov 02/2008 most of Canada went onto standard time. On Nov 03/2008 I +# phoned the Resolute Bay hamlet office...[D]ue to the challenging nature +# of the phone call, I decided to seek out an alternate source of +# information. I found an e-mail address for somebody by the name of +# Stephanie Adams whose job was listed as "Inns North Support Officer for +# Arctic Co-operatives." I was under the impression that Stephanie lived +# and worked in Resolute Bay... +# +# On March 14/2011 I phoned the hamlet office again. I was told that +# Resolute Bay had been using Central Standard Time over the winter of +# 2010-2011 and that the clocks had therefore been moved one hour ahead +# on March 13/2011. The person I talked to was aware that Resolute Bay +# had previously experimented with Eastern Standard Time but he could not +# tell me when the practice had stopped. +# +# On March 17/2011 I searched the Web to find an e-mail address of +# somebody that might be able to tell me exactly when Resolute Bay went +# off Eastern Standard Time. I stumbled on the name "Aziz Kheraj." Aziz +# used to be the mayor of Resolute Bay and he apparently owns half the +# businesses including "South Camp Inn." This website has some info on +# Aziz: +# http://www.uphere.ca/node/493 +# +# I sent Aziz an e-mail asking when Resolute Bay had stopped using +# Eastern Standard Time. +# +# Aziz responded quickly with this: "hi, The time was not changed for the +# 1 year only, the following year, the community went back to the old way +# of "spring ahead-fall behind" currently we are zulu plus 5 hrs and in +# the winter Zulu plus 6 hrs" +# +# This of course conflicted with everything I had ascertained in November 2008. +# +# I sent Aziz a copy of my 2008 e-mail exchange with Stephanie. Aziz +# responded with this: "Hi, Stephanie lives in Winnipeg. I live here, You +# may want to check with the weather office in Resolute Bay or do a +# search on the weather through Env. Canada. web site" +# +# If I had realized the Stephanie did not live in Resolute Bay I would +# never have contacted her. I now believe that all the information I +# obtained in November 2008 should be ignored... +# I apologize for reporting incorrect information in 2008. + +# From Tim Parenti (2020-03-05): +# The government of Yukon announced [yesterday] the cessation of seasonal time +# changes. "After clocks are pushed ahead one hour on March 8, the territory +# will remain on [UTC-07]. ... [The government] found 93 per cent of +# respondents wanted to end seasonal time changes and, of that group, 70 per +# cent wanted 'permanent Pacific Daylight Saving Time.'" +# https://www.cbc.ca/news/canada/north/yukon-end-daylight-saving-time-1.5486358 +# +# Although the government press release prefers PDT, we prefer MST for +# consistency with nearby Dawson Creek, Creston, and Fort Nelson. +# https://yukon.ca/en/news/yukon-end-seasonal-time-change + +# From Andrew G. Smith (2020-09-24): +# Yukon has completed its regulatory change to be on UTC -7 year-round.... +# http://www.gov.yk.ca/legislation/regs/oic2020_125.pdf +# What we have done is re-defined Yukon Standard Time, as we are +# authorized to do under section 33 of our Interpretation Act: +# http://www.gov.yk.ca/legislation/acts/interpretation_c.pdf +# +# From Paul Eggert (2020-09-24): +# tzdb uses the obsolete YST abbreviation for standard time in Yukon through +# about 1970, and uses PST for standard time in Yukon since then. Consistent +# with that, use MST for -07, the new standard time in Yukon effective Nov. 1. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule NT_YK 1918 only - Apr 14 2:00 1:00 D +Rule NT_YK 1918 only - Oct 27 2:00 0 S +Rule NT_YK 1919 only - May 25 2:00 1:00 D +Rule NT_YK 1919 only - Nov 1 0:00 0 S +Rule NT_YK 1942 only - Feb 9 2:00 1:00 W # War +Rule NT_YK 1945 only - Aug 14 23:00u 1:00 P # Peace +Rule NT_YK 1945 only - Sep 30 2:00 0 S +Rule NT_YK 1972 1986 - Apr lastSun 2:00 1:00 D +Rule NT_YK 1972 2006 - Oct lastSun 2:00 0 S +Rule NT_YK 1987 2006 - Apr Sun>=1 2:00 1:00 D +Rule Yukon 1965 only - Apr lastSun 0:00 2:00 DD +Rule Yukon 1965 only - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +# formerly Frobisher Bay +Zone America/Iqaluit 0 - -00 1942 Aug # Frobisher Bay est. + -5:00 NT_YK E%sT 1999 Oct 31 2:00 + -6:00 Canada C%sT 2000 Oct 29 2:00 + -5:00 Canada E%sT +# aka Qausuittuq +Zone America/Resolute 0 - -00 1947 Aug 31 # Resolute founded + -6:00 NT_YK C%sT 2000 Oct 29 2:00 + -5:00 - EST 2001 Apr 1 3:00 + -6:00 Canada C%sT 2006 Oct 29 2:00 + -5:00 - EST 2007 Mar 11 3:00 + -6:00 Canada C%sT +# aka Kangiqiniq +Zone America/Rankin_Inlet 0 - -00 1957 # Rankin Inlet founded + -6:00 NT_YK C%sT 2000 Oct 29 2:00 + -5:00 - EST 2001 Apr 1 3:00 + -6:00 Canada C%sT +# aka Iqaluktuuttiaq +Zone America/Cambridge_Bay 0 - -00 1920 # trading post est.? + -7:00 NT_YK M%sT 1999 Oct 31 2:00 + -6:00 Canada C%sT 2000 Oct 29 2:00 + -5:00 - EST 2000 Nov 5 0:00 + -6:00 - CST 2001 Apr 1 3:00 + -7:00 Canada M%sT +Zone America/Inuvik 0 - -00 1953 # Inuvik founded + -8:00 NT_YK P%sT 1979 Apr lastSun 2:00 + -7:00 NT_YK M%sT 1980 + -7:00 Canada M%sT +Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20 + -9:00 NT_YK Y%sT 1965 + -9:00 Yukon Y%sT 1966 Feb 27 0:00 + -8:00 - PST 1980 + -8:00 Canada P%sT 2020 Nov 1 + -7:00 - MST +Zone America/Dawson -9:17:40 - LMT 1900 Aug 20 + -9:00 NT_YK Y%sT 1965 + -9:00 Yukon Y%sT 1973 Oct 28 0:00 + -8:00 - PST 1980 + -8:00 Canada P%sT 2020 Nov 1 + -7:00 - MST + + +############################################################################### + +# Mexico + +# From Paul Eggert (2014-12-07): +# The Investigation and Analysis Service of the +# Mexican Library of Congress (MLoC) has published a +# history of Mexican local time (in Spanish) +# http://www.diputados.gob.mx/bibliot/publica/inveyana/polisoc/horver/index.htm +# +# Here are the discrepancies between Shanks & Pottenger (S&P) and the MLoC. +# (In all cases we go with the MLoC.) +# S&P report that Baja was at -8:00 in 1922/1923. +# S&P say the 1930 transition in Baja was 1930-11-16. +# S&P report no DST during summer 1931. +# S&P report a transition at 1932-03-30 23:00, not 1932-04-01. + +# From Gwillim Law (2001-02-20): +# There are some other discrepancies between the Decrees page and the +# tz database. I think they can best be explained by supposing that +# the researchers who prepared the Decrees page failed to find some of +# the relevant documents. + +# From Alan Perry (1996-02-15): +# A guy from our Mexico subsidiary finally found the Presidential Decree +# outlining the timezone changes in Mexico. +# +# ------------- Begin Forwarded Message ------------- +# +# I finally got my hands on the Official Presidential Decree that sets up the +# rules for the DST changes. The rules are: +# +# 1. The country is divided in 3 timezones: +# - Baja California Norte (the Mexico/BajaNorte TZ) +# - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ) +# - The rest of the country (the Mexico/General TZ) +# +# 2. From the first Sunday in April at 2:00 AM to the last Sunday in October +# at 2:00 AM, the times in each zone are as follows: +# BajaNorte: GMT+7 +# BajaSur: GMT+6 +# General: GMT+5 +# +# 3. The rest of the year, the times are as follows: +# BajaNorte: GMT+8 +# BajaSur: GMT+7 +# General: GMT+6 +# +# The Decree was published in Mexico's Official Newspaper on January 4th. +# +# -------------- End Forwarded Message -------------- +# From Paul Eggert (1996-06-12): +# For an English translation of the decree, see +# "Diario Oficial: Time Zone Changeover" (1996-01-04). +# http://mexico-travel.com/extra/timezone_eng.html + +# From Rives McDow (1998-10-08): +# The State of Quintana Roo has reverted back to central STD and DST times +# (i.e. UTC -0600 and -0500 as of 1998-08-02). + +# From Rives McDow (2000-01-10): +# Effective April 4, 1999 at 2:00 AM local time, Sonora changed to the time +# zone 5 hours from the International Date Line, and will not observe daylight +# savings time so as to stay on the same time zone as the southern part of +# Arizona year round. + +# From Jesper Nørgaard, translating +# <http://www.reforma.com/nacional/articulo/064327/> (2001-01-17): +# In Oaxaca, the 55.000 teachers from the Section 22 of the National +# Syndicate of Education Workers, refuse to apply daylight saving each +# year, so that the more than 10,000 schools work at normal hour the +# whole year. + +# From Gwillim Law (2001-01-19): +# <http://www.reforma.com/negocios_y_dinero/articulo/064481/> ... says +# (translated):... +# January 17, 2000 - The Energy Secretary, Ernesto Martens, announced +# that Summer Time will be reduced from seven to five months, starting +# this year.... +# http://www.publico.com.mx/scripts/texto3.asp?action=pagina&pag=21&pos=p&secc=naci&date=01/17/2001 +# [translated], says "summer time will ... take effect on the first Sunday +# in May, and end on the last Sunday of September. + +# From Arthur David Olson (2001-01-25): +# The 2001-01-24 traditional Washington Post contained the page one +# story "Timely Issue Divides Mexicans."... +# http://www.washingtonpost.com/wp-dyn/articles/A37383-2001Jan23.html +# ... Mexico City Mayor López Obrador "...is threatening to keep +# Mexico City and its 20 million residents on a different time than +# the rest of the country..." In particular, López Obrador would abolish +# observation of Daylight Saving Time. + +# Official statute published by the Energy Department +# http://www.conae.gob.mx/ahorro/decretohorver2001.html#decre +# (2001-02-01) shows Baja and Chihauhua as still using US DST rules, +# and Sonora with no DST. This was reported by Jesper Nørgaard (2001-02-03). + +# From Paul Eggert (2001-03-03): +# +# https://www.latimes.com/archives/la-xpm-2001-mar-03-mn-32561-story.html +# James F. Smith writes in today's LA Times +# * Sonora will continue to observe standard time. +# * Last week Mexico City's mayor Andrés Manuel López Obrador decreed that +# the Federal District will not adopt DST. +# * 4 of 16 district leaders announced they'll ignore the decree. +# * The decree does not affect federal-controlled facilities including +# the airport, banks, hospitals, and schools. +# +# For now we'll assume that the Federal District will bow to federal rules. + +# From Jesper Nørgaard (2001-04-01): +# I found some references to the Mexican application of daylight +# saving, which modifies what I had already sent you, stating earlier +# that a number of northern Mexican states would go on daylight +# saving. The modification reverts this to only cover Baja California +# (Norte), while all other states (except Sonora, who has no daylight +# saving all year) will follow the original decree of president +# Vicente Fox, starting daylight saving May 6, 2001 and ending +# September 30, 2001. +# References: "Diario de Monterrey" <http://www.diariodemonterrey.com/index.asp> +# Palabra <http://palabra.infosel.com/010331/primera/ppri3101.pdf> (2001-03-31) + +# From Reuters (2001-09-04): +# Mexico's Supreme Court on Tuesday declared that daylight savings was +# unconstitutional in Mexico City, creating the possibility the +# capital will be in a different time zone from the rest of the nation +# next year.... The Supreme Court's ruling takes effect at 2:00 +# a.m. (0800 GMT) on Sept. 30, when Mexico is scheduled to revert to +# standard time. "This is so residents of the Federal District are not +# subject to unexpected time changes," a statement from the court said. + +# From Jesper Nørgaard Welen (2002-03-12): +# ... consulting my local grocery store(!) and my coworkers, they all insisted +# that a new decision had been made to reinstate US style DST in Mexico.... +# http://www.conae.gob.mx/ahorro/horaver2001_m1_2002.html (2002-02-20) +# confirms this. Sonora as usual is the only state where DST is not applied. + +# From Steffen Thorsen (2009-12-28): +# +# Steffen Thorsen wrote: +# > Mexico's House of Representatives has approved a proposal for northern +# > Mexico's border cities to share the same daylight saving schedule as +# > the United States. +# Now this has passed both the Congress and the Senate, so starting from +# 2010, some border regions will be the same: +# http://www.signonsandiego.com/news/2009/dec/28/clocks-will-match-both-sides-border/ +# http://www.elmananarey.com/diario/noticia/nacional/noticias/empatan_horario_de_frontera_con_eu/621939 +# (Spanish) +# +# Could not find the new law text, but the proposed law text changes are here: +# http://gaceta.diputados.gob.mx/Gaceta/61/2009/dic/20091210-V.pdf +# (Gaceta Parlamentaria) +# +# There is also a list of the votes here: +# http://gaceta.diputados.gob.mx/Gaceta/61/2009/dic/V2-101209.html +# +# Our page: +# https://www.timeanddate.com/news/time/north-mexico-dst-change.html + +# From Arthur David Olson (2010-01-20): +# The page +# http://dof.gob.mx/nota_detalle.php?codigo=5127480&fecha=06/01/2010 +# includes this text: +# En los municipios fronterizos de Tijuana y Mexicali en Baja California; +# Juárez y Ojinaga en Chihuahua; Acuña y Piedras Negras en Coahuila; +# Anáhuac en Nuevo León; y Nuevo Laredo, Reynosa y Matamoros en +# Tamaulipas, la aplicación de este horario estacional surtirá efecto +# desde las dos horas del segundo domingo de marzo y concluirá a las dos +# horas del primer domingo de noviembre. +# En los municipios fronterizos que se encuentren ubicados en la franja +# fronteriza norte en el territorio comprendido entre la línea +# internacional y la línea paralela ubicada a una distancia de veinte +# kilómetros, así como la Ciudad de Ensenada, Baja California, hacia el +# interior del país, la aplicación de este horario estacional surtirá +# efecto desde las dos horas del segundo domingo de marzo y concluirá a +# las dos horas del primer domingo de noviembre. + +# From Steffen Thorsen (2014-12-08), translated by Gwillim Law: +# The Mexican state of Quintana Roo will likely change to EST in 2015. +# +# http://www.unioncancun.mx/articulo/2014/12/04/medio-ambiente/congreso-aprueba-una-hora-mas-de-sol-en-qroo +# "With this change, the time conflict that has existed between the municipios +# of Quintana Roo and the municipio of Felipe Carrillo Puerto may come to an +# end. The latter declared itself in rebellion 15 years ago when a time change +# was initiated in Mexico, and since then it has refused to change its time +# zone along with the rest of the country." +# +# From Steffen Thorsen (2015-01-14), translated by Gwillim Law: +# http://sipse.com/novedades/confirman-aplicacion-de-nueva-zona-horaria-para-quintana-roo-132331.html +# "...the new time zone will come into effect at two o'clock on the first Sunday +# of February, when we will have to advance the clock one hour from its current +# time..." +# Also, the new zone will not use DST. +# +# From Carlos Raúl Perasso (2015-02-02): +# The decree that modifies the Mexican Hour System Law has finally +# been published at the Diario Oficial de la Federación +# http://www.dof.gob.mx/nota_detalle.php?codigo=5380123&fecha=31/01/2015 +# It establishes 5 zones for Mexico: +# 1- Zona Centro (Central Zone): Corresponds to longitude 90 W, +# includes most of Mexico, excluding what's mentioned below. +# 2- Zona Pacífico (Pacific Zone): Longitude 105 W, includes the +# states of Baja California Sur; Chihuahua; Nayarit (excluding Bahía +# de Banderas which lies in Central Zone); Sinaloa and Sonora. +# 3- Zona Noroeste (Northwest Zone): Longitude 120 W, includes the +# state of Baja California. +# 4- Zona Sureste (Southeast Zone): Longitude 75 W, includes the state +# of Quintana Roo. +# 5- The islands, reefs and keys shall take their timezone from the +# longitude they are located at. + +# From Paul Eggert (2022-10-28): +# The new Mexican law was published today: +# https://www.dof.gob.mx/nota_detalle.php?codigo=5670045&fecha=28/10/2022 +# This abolishes DST except where US DST rules are observed, +# and in addition changes all of Chihuahua to -06 with no DST. + +# From Heitor David Pinto (2022-11-28): +# Now the northern [municipios] want to have the same time zone as the +# respective neighboring cities in the US, for example Juárez in UTC-7 with +# DST, matching El Paso, and Ojinaga in UTC-6 with DST, matching Presidio.... +# the president authorized the publication of the decree for November 29, +# so the time change would occur on November 30 at 0:00. +# http://puentelibre.mx/noticia/ciudad_juarez_cambio_horario_noviembre_2022/ + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Mexico 1931 only - May 1 23:00 1:00 D +Rule Mexico 1931 only - Oct 1 0:00 0 S +Rule Mexico 1939 only - Feb 5 0:00 1:00 D +Rule Mexico 1939 only - Jun 25 0:00 0 S +Rule Mexico 1940 only - Dec 9 0:00 1:00 D +Rule Mexico 1941 only - Apr 1 0:00 0 S +Rule Mexico 1943 only - Dec 16 0:00 1:00 W # War +Rule Mexico 1944 only - May 1 0:00 0 S +Rule Mexico 1950 only - Feb 12 0:00 1:00 D +Rule Mexico 1950 only - Jul 30 0:00 0 S +Rule Mexico 1996 2000 - Apr Sun>=1 2:00 1:00 D +Rule Mexico 1996 2000 - Oct lastSun 2:00 0 S +Rule Mexico 2001 only - May Sun>=1 2:00 1:00 D +Rule Mexico 2001 only - Sep lastSun 2:00 0 S +Rule Mexico 2002 2022 - Apr Sun>=1 2:00 1:00 D +Rule Mexico 2002 2022 - Oct lastSun 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +# Quintana Roo; represented by Cancún +Zone America/Cancun -5:47:04 - LMT 1922 Jan 1 6:00u + -6:00 - CST 1981 Dec 23 + -5:00 Mexico E%sT 1998 Aug 2 2:00 + -6:00 Mexico C%sT 2015 Feb 1 2:00 + -5:00 - EST +# Campeche, Yucatán; represented by Mérida +Zone America/Merida -5:58:28 - LMT 1922 Jan 1 6:00u + -6:00 - CST 1981 Dec 23 + -5:00 - EST 1982 Dec 2 + -6:00 Mexico C%sT +# Coahuila, Nuevo León, Tamaulipas (near US border) +# This includes the following municipios: +# in Coahuila: Acuña, Allende, Guerrero, Hidalgo, Jiménez, Morelos, Nava, +# Ocampo, Piedras Negras, Villa Unión, Zaragoza +# in Nuevo León: Anáhuac +# in Tamaulipas: Nuevo Laredo, Guerrero, Mier, Miguel Alemán, Camargo, +# Gustavo Díaz Ordaz, Reynosa, Río Bravo, Valle Hermoso, Matamoros. +# https://www.dof.gob.mx/nota_detalle.php?codigo=5670045&fecha=28/10/2022 +Zone America/Matamoros -6:30:00 - LMT 1922 Jan 1 6:00u + -6:00 - CST 1988 + -6:00 US C%sT 1989 + -6:00 Mexico C%sT 2010 + -6:00 US C%sT +# Durango; Coahuila, Nuevo León, Tamaulipas (away from US border) +Zone America/Monterrey -6:41:16 - LMT 1922 Jan 1 6:00u + -6:00 - CST 1988 + -6:00 US C%sT 1989 + -6:00 Mexico C%sT +# Central Mexico +Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 7:00u + -7:00 - MST 1927 Jun 10 23:00 + -6:00 - CST 1930 Nov 15 + -7:00 Mexico M%sT 1932 Apr 1 + -6:00 Mexico C%sT 2001 Sep 30 2:00 + -6:00 - CST 2002 Feb 20 + -6:00 Mexico C%sT +# Chihuahua (near US border - western side) +# This includes the municipios of Janos, Ascensión, Juárez, Guadalupe, and +# Práxedis G Guerrero. +# http://gaceta.diputados.gob.mx/PDF/65/2a022/nov/20221124-VII.pdf +Zone America/Ciudad_Juarez -7:05:56 - LMT 1922 Jan 1 7:00u + -7:00 - MST 1927 Jun 10 23:00 + -6:00 - CST 1930 Nov 15 + -7:00 Mexico M%sT 1932 Apr 1 + -6:00 - CST 1996 + -6:00 Mexico C%sT 1998 + -6:00 - CST 1998 Apr Sun>=1 3:00 + -7:00 Mexico M%sT 2010 + -7:00 US M%sT 2022 Oct 30 2:00 + -6:00 - CST 2022 Nov 30 0:00 + -7:00 US M%sT +# Chihuahua (near US border - eastern side) +# This includes the municipios of Coyame del Sotol, Ojinaga, and Manuel +# Benavides. +# http://gaceta.diputados.gob.mx/PDF/65/2a022/nov/20221124-VII.pdf +Zone America/Ojinaga -6:57:40 - LMT 1922 Jan 1 7:00u + -7:00 - MST 1927 Jun 10 23:00 + -6:00 - CST 1930 Nov 15 + -7:00 Mexico M%sT 1932 Apr 1 + -6:00 - CST 1996 + -6:00 Mexico C%sT 1998 + -6:00 - CST 1998 Apr Sun>=1 3:00 + -7:00 Mexico M%sT 2010 + -7:00 US M%sT 2022 Oct 30 2:00 + -6:00 - CST 2022 Nov 30 0:00 + -6:00 US C%sT +# Chihuahua (away from US border) +Zone America/Chihuahua -7:04:20 - LMT 1922 Jan 1 7:00u + -7:00 - MST 1927 Jun 10 23:00 + -6:00 - CST 1930 Nov 15 + -7:00 Mexico M%sT 1932 Apr 1 + -6:00 - CST 1996 + -6:00 Mexico C%sT 1998 + -6:00 - CST 1998 Apr Sun>=1 3:00 + -7:00 Mexico M%sT 2022 Oct 30 2:00 + -6:00 - CST +# Sonora +Zone America/Hermosillo -7:23:52 - LMT 1922 Jan 1 7:00u + -7:00 - MST 1927 Jun 10 23:00 + -6:00 - CST 1930 Nov 15 + -7:00 Mexico M%sT 1932 Apr 1 + -6:00 - CST 1942 Apr 24 + -7:00 - MST 1949 Jan 14 + -8:00 - PST 1970 + -7:00 Mexico M%sT 1999 + -7:00 - MST + +# Baja California Sur, Nayarit (except Bahía de Banderas), Sinaloa +Zone America/Mazatlan -7:05:40 - LMT 1922 Jan 1 7:00u + -7:00 - MST 1927 Jun 10 23:00 + -6:00 - CST 1930 Nov 15 + -7:00 Mexico M%sT 1932 Apr 1 + -6:00 - CST 1942 Apr 24 + -7:00 - MST 1949 Jan 14 + -8:00 - PST 1970 + -7:00 Mexico M%sT + +# Bahía de Banderas + +# From Alexander Krivenyshev (2010-04-21): +# According to news, Bahía de Banderas (Mexican state of Nayarit) +# changed time zone UTC-7 to new time zone UTC-6 on April 4, 2010 (to +# share the same time zone as nearby city Puerto Vallarta, Jalisco). +# +# (Spanish) +# Bahía de Banderas homologa su horario al del centro del +# país, a partir de este domingo +# http://www.nayarit.gob.mx/notes.asp?id=20748 +# +# Bahía de Banderas homologa su horario con el del Centro del +# País +# http://www.bahiadebanderas.gob.mx/principal/index.php?option=com_content&view=article&id=261:bahia-de-banderas-homologa-su-horario-con-el-del-centro-del-pais&catid=42:comunicacion-social&Itemid=50 +# +# (English) +# Puerto Vallarta and Bahía de Banderas: One Time Zone +# http://virtualvallarta.com/puertovallarta/puertovallarta/localnews/2009-12-03-Puerto-Vallarta-and-Bahia-de-Banderas-One-Time-Zone.shtml +# http://www.worldtimezone.com/dst_news/dst_news_mexico08.html +# +# "Mexico's Senate approved the amendments to the Mexican Schedule System that +# will allow Bahía de Banderas and Puerto Vallarta to share the same time +# zone ..." +# Baja California Sur, Nayarit, Sinaloa + +# From Arthur David Olson (2010-05-01): +# Use "Bahia_Banderas" to keep the name to fourteen characters. + +Zone America/Bahia_Banderas -7:01:00 - LMT 1922 Jan 1 7:00u + -7:00 - MST 1927 Jun 10 23:00 + -6:00 - CST 1930 Nov 15 + -7:00 Mexico M%sT 1932 Apr 1 + -6:00 - CST 1942 Apr 24 + -7:00 - MST 1949 Jan 14 + -8:00 - PST 1970 + -7:00 Mexico M%sT 2010 Apr 4 2:00 + -6:00 Mexico C%sT + +# Baja California +Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 7:00u + -7:00 - MST 1924 + -8:00 - PST 1927 Jun 10 23:00 + -7:00 - MST 1930 Nov 15 + -8:00 - PST 1931 Apr 1 + -8:00 1:00 PDT 1931 Sep 30 + -8:00 - PST 1942 Apr 24 + -8:00 1:00 PWT 1945 Aug 14 23:00u + -8:00 1:00 PPT 1945 Nov 12 # Peace + -8:00 - PST 1948 Apr 5 + -8:00 1:00 PDT 1949 Jan 14 + -8:00 - PST 1954 + -8:00 CA P%sT 1961 + -8:00 - PST 1976 + -8:00 US P%sT 1996 + -8:00 Mexico P%sT 2001 + -8:00 US P%sT 2002 Feb 20 + -8:00 Mexico P%sT 2010 + -8:00 US P%sT +# From Paul Eggert (2006-03-22): +# Formerly there was an America/Ensenada zone, which differed from +# America/Tijuana only in that it did not observe DST from 1976 +# through 1995. This was as per Shanks (1999). But Shanks & Pottenger say +# Ensenada did not observe DST from 1948 through 1975. Guy Harris reports +# that the 1987 OAG says "Only Ensenada, Mexicali, San Felipe and +# Tijuana observe DST," which agrees with Shanks & Pottenger but implies that +# DST-observance was a town-by-town matter back then. This concerns +# data after 1970 so most likely there should be at least one Zone +# other than America/Tijuana for Baja, but it's not clear yet what its +# name or contents should be. +# +# From Paul Eggert (2015-10-08): +# Formerly there was an America/Santa_Isabel zone, but this appears to +# have come from a misreading of +# http://dof.gob.mx/nota_detalle.php?codigo=5127480&fecha=06/01/2010 +# It has been moved to the 'backward' file. +# +# From Paul Eggert (2022-10-28): +# Today's new law states that the entire state of Baja California +# follows US DST rules, which agrees with simplifications noted above. +# +# +# Revillagigedo Is +# no information + +############################################################################### + +# Barbados + +# For 1899 Milne gives -3:58:29.2. + +# From P Chan (2020-12-09 and 2020-12-11): +# Standard time of GMT-4 was adopted in 1911. +# Definition of Time Act, 1911 (1911-7) [1911-08-28] +# 1912, Laws of Barbados (5 v.), OCLC Number: 919801291, Vol. 4, Image No. 522 +# 1944, Laws of Barbados (5 v.), OCLC Number: 84548697, Vol. 4, Image No. 122 +# http://llmc.com/browse.aspx?type=2&coll=85&div=297 +# +# DST was observed in 1942-44. +# Defence (Daylight Saving) Regulations, 1942, 1942-04-13 +# Defence (Daylight Saving) (Repeal) Regulations, 1942, 1942-08-22 +# Defence (Daylight Saving) Regulations, 1943, 1943-04-16 +# Defence (Daylight Saving) (Repeal) Regulations, 1943, 1943-09-01 +# Defence (Daylight Saving) Regulations, 1944, 1944-03-21 +# [Defence (Daylight Saving) (Amendment) Regulations 1944, 1944-03-28] +# Defence (Daylight Saving) (Repeal) Regulations, 1944, 1944-08-30 +# +# 1914-, Subsidiary Legis., Annual Vols. OCLC Number: 226290591 +# 1942: Image Nos. 527-528, 555-556 +# 1943: Image Nos. 178-179, 198 +# 1944: Image Nos. 113-115, 129 +# http://llmc.com/titledescfull.aspx?type=2&coll=85&div=297&set=98437 +# +# From Tim Parenti (2021-02-20): +# The transitions below are derived from P Chan's sources, except that the 1977 +# through 1980 transitions are from Shanks & Pottenger since we have no better +# data there. Of particular note, the 1944 DST regulation only advanced the +# time to "exactly three and a half hours later than Greenwich mean time", as +# opposed to "three hours" in the 1942 and 1943 regulations. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Barb 1942 only - Apr 19 5:00u 1:00 D +Rule Barb 1942 only - Aug 31 6:00u 0 S +Rule Barb 1943 only - May 2 5:00u 1:00 D +Rule Barb 1943 only - Sep 5 6:00u 0 S +Rule Barb 1944 only - Apr 10 5:00u 0:30 - +Rule Barb 1944 only - Sep 10 6:00u 0 S +Rule Barb 1977 only - Jun 12 2:00 1:00 D +Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S +Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D +Rule Barb 1979 only - Sep 30 2:00 0 S +Rule Barb 1980 only - Sep 25 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] + #STDOFF -3:58:29.2 +Zone America/Barbados -3:58:29 - LMT 1911 Aug 28 # Bridgetown + -4:00 Barb A%sT 1944 + -4:00 Barb AST/-0330 1945 + -4:00 Barb A%sT + +# Belize + +# From P Chan (2020-11-03): +# Below are some laws related to the time in British Honduras/Belize: +# +# Definition of Time Ordinance, 1927 (No.4 of 1927) [1927-04-01] +# Ordinances of British Honduras Passed in the Year 1927, p 19-20 +# https://books.google.com/books?id=LqEpAQAAMAAJ&pg=RA3-PA19 +# +# Definition of Time (Amendment) Ordinance, 1942 (No. 5 of 1942) [1942-06-27] +# Ordinances of British Honduras Passed in the Year 1942, p 31-32 +# https://books.google.com/books?id=h6MpAQAAMAAJ&pg=RA6-PA95-IA44 +# +# Definition of Time Ordinance, 1945 (No. 19 of 1945) [1945-12-15] +# Ordinances of British Honduras Passed in the Year 1945, p 49-50 +# https://books.google.com/books?id=xaMpAQAAMAAJ&pg=RA2-PP1 +# +# Definition of Time Ordinance, 1947 (No. 1 of 1947) [1947-03-11] +# Ordinances of British Honduras Passed in the Year 1947, p 1-2 +# https://books.google.com/books?id=xaMpAQAAMAAJ&pg=RA3-PA1 +# +# Time (Definition of) Ordinance (Chapter 180) +# The Laws of British Honduras in Force on the 15th Day of September, 1958 , Volume IV, p 2580 +# https://books.google.com/books?id=v5QpAQAAMAAJ&pg=PA2580 +# +# Time (Definition of) (Amendment) Ordinance, 1968 (No. 13 of 1968) [1968-08-03] +# https://books.google.com/books?id=xij7KEB_58wC&pg=RA1-PA428-IA9 +# +# Definition of Time Act (Chapter 339) +# Law of Belize, Revised Edition 2000 +# http://www.belizelaw.org/web/lawadmin/PDF%20files/cap339.pdf + +# From Paul Eggert (2020-11-03): +# The transitions below are derived from P Chan's sources, except that the +# 1973 through 1983 transitions are from Shanks & Pottenger since we have +# no better data there. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Belize 1918 1941 - Oct Sat>=1 24:00 0:30 -0530 +Rule Belize 1919 1942 - Feb Sat>=8 24:00 0 CST +Rule Belize 1942 only - Jun 27 24:00 1:00 CWT +Rule Belize 1945 only - Aug 14 23:00u 1:00 CPT +Rule Belize 1945 only - Dec 15 24:00 0 CST +Rule Belize 1947 1967 - Oct Sat>=1 24:00 0:30 -0530 +Rule Belize 1948 1968 - Feb Sat>=8 24:00 0 CST +Rule Belize 1973 only - Dec 5 0:00 1:00 CDT +Rule Belize 1974 only - Feb 9 0:00 0 CST +Rule Belize 1982 only - Dec 18 0:00 1:00 CDT +Rule Belize 1983 only - Feb 12 0:00 0 CST +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Belize -5:52:48 - LMT 1912 Apr 1 + -6:00 Belize %s + +# Bermuda + +# From Paul Eggert (2022-07-27): +# For 1899 Milne gives -4:19:18.3 as the meridian of the clock tower, +# Bermuda dockyard, Ireland I. This agrees with standard offset given in the +# Daylight Saving Act, 1917 cited below. +# It is not known when this time became standard for Bermuda; guess 1890. +# The transition to -04 was specified by: +# 1930: The Time Zone Act, 1929 (1929: No. 39) [1929-11-08] +# https://books.google.com/books?id=7tdMAQAAIAAJ&pg=RA54-PP1 + +# From P Chan (2020-11-20): +# Most of the information can be found online from the Bermuda National +# Library - Digital Collection which includes The Royal Gazette (RG) until 1957 +# https://bnl.contentdm.oclc.org/digital/ +# I will cite the ID. For example, [10000] means +# https://bnl.contentdm.oclc.org/digital/collection/BermudaNP02/id/10000 +# +# 1917: Apr 5 midnight to Sep 30 midnight +# Daylight Saving Act, 1917 (1917 No. 13) [1917-04-02] +# Bermuda Acts and Resolves 1917, p 37-38 +# https://books.google.com/books?id=M-lCAQAAMAAJ&pg=PA36-IA2 +# RG, 1917-04-04, p 6 [42340] gives the spring forward date. +# +# 1918: Apr 13 midnight to Sep 15 midnight +# Daylight Saving Act, 1918 (1918 No. 9) [1918-04-06] +# Bermuda Acts and Resolves 1917, p 13 +# https://books.google.com/books?id=K-lCAQAAMAAJ&pg=RA1-PA7 +# +# Note that local mean time was still used before 1930. +# +# During WWII, DST was introduced by Defence Regulations +# 1942: Jan 11 02:00 to Oct 18 02:00 [113646], [115726] +# 1943: Mar 21 02:00 to Oct 31 02:00 [116704], [118193] +# 1944: Mar 12 02:00 to Nov 5 02:00 [119225], [121593] +# 1945: Mar 11 02:00 to Nov 4 02:00 [122369], [124461] +# RG, 1942-01-08, p 2, 1942-10-12, p 2 , 1943-03-06, p 2, 1943-09-03, p 1, +# 1944-02-29, p 6, 1944-09-20, p 2, 1945-02-13, p 2, 1945-11-03, p 1 +# +# In 1946, the House of Assembly rejected DST twice. [128686], [128076] +# RG, 1946-03-16 p 1,1946-04-13 p 1 +# +# 1947: third Sunday in May 02:00 to second Sunday in September 02:00 +# DST in 1947 was defined in the Daylight Saving Act, 1947 (1947: No. 12) +# which expired at the end of the year. [125784] ,[132405], [144454], [138226] +# RG, 1947-02-27, p 1, 1947-05-15, p 1, 1947-09-13, p 1, 1947-12-30, p 1 +# +# 1948-1952: fourth Sunday in May 02:00 to first Sunday in September 02:00 +# DST in 1948 was defined in the Daylight Saving Act, 1948 (1948 : No. 12) +# which was set to expired at the end of the year but it was extended until +# the end of 1952 and was not further extended. +# [129802], [139403], [146008], [135240], [144330], [139049], [143309], +# [148271], [149773], [153589], [153802], [155924] +# RG, 1948-04-13, p 1, 1948-05-22, p 1, 1948-09-04, p 1, 1949-05-21, p1, +# 1949-09-03, p 1, 1950-05-27 p 1, 1950-09-02, p 1, 1951-05-27, p 1, +# 1951-09-01, p 1, 1952-05-23, p 1, 1952-09-26, p 1, 1952-12-21, p 8 +# +# In 1953-1955, the House of Assembly rejected DST each year. [158996], +# [162620], [166720] RG, 1953-05-02, p 1, 1954-04-01 p 1, 1955-03-12, p 1 +# +# 1956: fourth Sunday in May 02:00 to last Sunday in October 02:00 +# Time Zone (Seasonal Variation) Act, 1956 (1956: No.44) [1956-05-25] +# Bermuda Public Acts 1956, p 331-332 +# https://books.google.com/books?id=Xs1AlmD_cEwC&pg=PA63 +# +# The extension of the Act was rejected by the House of Assembly. [176218] +# RG, 1956-12-13, p 1 +# +# From the Chronological Table of Public and Private Acts up to 1985, it seems +# that there does not exist other Acts related to DST before 1973. +# https://books.google.com/books?id=r9hMAQAAIAAJ&pg=RA23-PA1 +# Public Acts of the Legislature of the Islands of Bermuda, Together with +# Statutory Instruments in Force Thereunder, Vol VII + +# From Dan Jones, reporting in The Royal Gazette (2006-06-26): +# Next year, however, clocks in the US will go forward on the second Sunday +# in March, until the first Sunday in November. And, after the Time Zone +# (Seasonal Variation) Bill 2006 was passed in the House of Assembly on +# Friday, the same thing will happen in Bermuda. +# http://www.theroyalgazette.com/apps/pbcs.dll/article?AID=/20060529/NEWS/105290135 + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Bermuda 1917 only - Apr 5 24:00 1:00 - +Rule Bermuda 1917 only - Sep 30 24:00 0 - +Rule Bermuda 1918 only - Apr 13 24:00 1:00 - +Rule Bermuda 1918 only - Sep 15 24:00 0 S +Rule Bermuda 1942 only - Jan 11 2:00 1:00 D +Rule Bermuda 1942 only - Oct 18 2:00 0 S +Rule Bermuda 1943 only - Mar 21 2:00 1:00 D +Rule Bermuda 1943 only - Oct 31 2:00 0 S +Rule Bermuda 1944 1945 - Mar Sun>=8 2:00 1:00 D +Rule Bermuda 1944 1945 - Nov Sun>=1 2:00 0 S +Rule Bermuda 1947 only - May Sun>=15 2:00 1:00 D +Rule Bermuda 1947 only - Sep Sun>=8 2:00 0 S +Rule Bermuda 1948 1952 - May Sun>=22 2:00 1:00 D +Rule Bermuda 1948 1952 - Sep Sun>=1 2:00 0 S +Rule Bermuda 1956 only - May Sun>=22 2:00 1:00 D +Rule Bermuda 1956 only - Oct lastSun 2:00 0 S + +# Zone NAME STDOFF RULES FORMAT [UNTIL] + #STDOFF -4:19:18.3 +Zone Atlantic/Bermuda -4:19:18 - LMT 1890 # Hamilton + -4:19:18 Bermuda BMT/BST 1930 Jan 1 2:00 + -4:00 Bermuda A%sT 1974 Apr 28 2:00 + -4:00 Canada A%sT 1976 + -4:00 US A%sT + +# Costa Rica + +# Milne gives -5:36:13.3 as San José mean time. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D +Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S +Rule CR 1991 1992 - Jan Sat>=15 0:00 1:00 D +# IATA SSIM (1991-09) says the following was at 1:00; +# go with Shanks & Pottenger. +Rule CR 1991 only - Jul 1 0:00 0 S +Rule CR 1992 only - Mar 15 0:00 0 S +# There are too many San Josés elsewhere, so we'll use 'Costa Rica'. +# Zone NAME STDOFF RULES FORMAT [UNTIL] + #STDOFF -5:36:13.3 +Zone America/Costa_Rica -5:36:13 - LMT 1890 # San José + -5:36:13 - SJMT 1921 Jan 15 # San José Mean Time + -6:00 CR C%sT +# Coco +# no information; probably like America/Costa_Rica + +# Cuba + +# From Paul Eggert (2013-02-21): +# Milne gives -5:28:50.45 for the observatory at Havana, -5:29:23.57 +# for the port, and -5:30 for meteorological observations. +# For now, stick with Shanks & Pottenger. + +# From Arthur David Olson (1999-03-29): +# The 1999-03-28 exhibition baseball game held in Havana, Cuba, between +# the Cuban National Team and the Baltimore Orioles was carried live on +# the Orioles Radio Network, including affiliate WTOP in Washington, DC. +# During the game, play-by-play announcer Jim Hunter noted that +# "We'll be losing two hours of sleep...Cuba switched to Daylight Saving +# Time today." (The "two hour" remark referred to losing one hour of +# sleep on 1999-03-28 - when the announcers were in Cuba as it switched +# to DST - and one more hour on 1999-04-04 - when the announcers will have +# returned to Baltimore, which switches on that date.) + +# From Steffen Thorsen (2013-11-11): +# DST start in Cuba in 2004 ... does not follow the same rules as the +# years before. The correct date should be Sunday 2004-03-28 00:00 ... +# https://web.archive.org/web/20040402060750/http://www.granma.cu/espanol/2004/marzo/sab27/reloj.html + +# From Evert van der Veer via Steffen Thorsen (2004-10-28): +# Cuba is not going back to standard time this year. +# From Paul Eggert (2006-03-22): +# http://www.granma.cu/ingles/2004/septiembre/juev30/41medid-i.html +# says that it's due to a problem at the Antonio Guiteras +# thermoelectric plant, and says "This October there will be no return +# to normal hours (after daylight saving time)". +# For now, let's assume that it's a temporary measure. + +# From Carlos A. Carnero Delgado (2005-11-12): +# This year (just like in 2004-2005) there's no change in time zone +# adjustment in Cuba. We will stay in daylight saving time: +# http://www.granma.cu/espanol/2005/noviembre/mier9/horario.html + +# From Jesper Nørgaard Welen (2006-10-21): +# An article in GRANMA INTERNACIONAL claims that Cuba will end +# the 3 years of permanent DST next weekend, see +# http://www.granma.cu/ingles/2006/octubre/lun16/43horario.html +# "On Saturday night, October 28 going into Sunday, October 29, at 01:00, +# watches should be set back one hour - going back to 00:00 hours - returning +# to the normal schedule.... + +# From Paul Eggert (2007-03-02): +# <http://www.granma.cubaweb.cu/english/news/art89.html>, dated yesterday, +# says Cuban clocks will advance at midnight on March 10. +# For lack of better information, assume Cuba will use US rules, +# except that it switches at midnight standard time as usual. +# +# From Steffen Thorsen (2007-10-25): +# Carlos Alberto Fonseca Arauz informed me that Cuba will end DST one week +# earlier - on the last Sunday of October, just like in 2006. +# +# He supplied these references: +# +# http://www.prensalatina.com.mx/article.asp?ID={4CC32C1B-A9F7-42FB-8A07-8631AFC923AF}&language=ES +# http://actualidad.terra.es/sociedad/articulo/cuba_llama_ahorrar_energia_cambio_1957044.htm +# +# From Alex Krivenyshev (2007-10-25): +# Here is also article from Granma (Cuba): +# +# Regirá el Horario Normal desde el próximo domingo 28 de octubre +# http://www.granma.cubaweb.cu/2007/10/24/nacional/artic07.html +# +# http://www.worldtimezone.com/dst_news/dst_news_cuba03.html + +# From Arthur David Olson (2008-03-09): +# I'm in Maryland which is now observing United States Eastern Daylight +# Time. At 9:44 local time I used RealPlayer to listen to +# http://media.enet.cu/radioreloj +# a Cuban information station, and heard +# the time announced as "ocho cuarenta y cuatro" ("eight forty-four"), +# indicating that Cuba is still on standard time. + +# From Steffen Thorsen (2008-03-12): +# It seems that Cuba will start DST on Sunday, 2007-03-16... +# It was announced yesterday, according to this source (in Spanish): +# http://www.nnc.cubaweb.cu/marzo-2008/cien-1-11-3-08.htm +# +# Some more background information is posted here: +# https://www.timeanddate.com/news/time/cuba-starts-dst-march-16.html +# +# The article also says that Cuba has been observing DST since 1963, +# while Shanks (and tzdata) has 1965 as the first date (except in the +# 1940's). Many other web pages in Cuba also claim that it has been +# observed since 1963, but with the exception of 1970 - an exception +# which is not present in tzdata/Shanks. So there is a chance we need to +# change some historic records as well. +# +# One example: +# http://www.radiohc.cu/espanol/noticias/mar07/11mar/hor.htm + +# From Jesper Nørgaard Welen (2008-03-13): +# The Cuban time change has just been confirmed on the most authoritative +# web site, the Granma. Please check out +# http://www.granma.cubaweb.cu/2008/03/13/nacional/artic10.html +# +# Basically as expected after Steffen Thorsen's information, the change +# will take place midnight between Saturday and Sunday. + +# From Arthur David Olson (2008-03-12): +# Assume Sun>=15 (third Sunday) going forward. + +# From Alexander Krivenyshev (2009-03-04) +# According to the Radio Reloj - Cuba will start Daylight Saving Time on +# midnight between Saturday, March 07, 2009 and Sunday, March 08, 2009- +# not on midnight March 14 / March 15 as previously thought. +# +# http://www.worldtimezone.com/dst_news/dst_news_cuba05.html +# (in Spanish) + +# From Arthur David Olson (2009-03-09) +# I listened over the Internet to +# http://media.enet.cu/readioreloj +# this morning; when it was 10:05 a. m. here in Bethesda, Maryland the +# the time was announced as "diez cinco" - the same time as here, indicating +# that has indeed switched to DST. Assume second Sunday from 2009 forward. + +# From Steffen Thorsen (2011-03-08): +# Granma announced that Cuba is going to start DST on 2011-03-20 00:00:00 +# this year. Nothing about the end date known so far (if that has +# changed at all). +# +# Source: +# http://granma.co.cu/2011/03/08/nacional/artic01.html +# +# Our info: +# https://www.timeanddate.com/news/time/cuba-starts-dst-2011.html +# +# From Steffen Thorsen (2011-10-30) +# Cuba will end DST two weeks later this year. Instead of going back +# tonight, it has been delayed to 2011-11-13 at 01:00. +# +# One source (Spanish) +# http://www.radioangulo.cu/noticias/cuba/17105-cuba-restablecera-el-horario-del-meridiano-de-greenwich.html +# +# Our page: +# https://www.timeanddate.com/news/time/cuba-time-changes-2011.html +# +# From Steffen Thorsen (2012-03-01) +# According to Radio Reloj, Cuba will start DST on Midnight between March +# 31 and April 1. +# +# Radio Reloj has the following info (Spanish): +# http://www.radioreloj.cu/index.php/noticias-radio-reloj/71-miscelaneas/7529-cuba-aplicara-el-horario-de-verano-desde-el-1-de-abril +# +# Our info on it: +# https://www.timeanddate.com/news/time/cuba-starts-dst-2012.html + +# From Steffen Thorsen (2012-11-03): +# Radio Reloj and many other sources report that Cuba is changing back +# to standard time on 2012-11-04: +# http://www.radioreloj.cu/index.php/noticias-radio-reloj/36-nacionales/9961-regira-horario-normal-en-cuba-desde-el-domingo-cuatro-de-noviembre +# From Paul Eggert (2012-11-03): +# For now, assume the future rule is first Sunday in November. + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Cuba 1928 only - Jun 10 0:00 1:00 D +Rule Cuba 1928 only - Oct 10 0:00 0 S +Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D +Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S +Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D +Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S +Rule Cuba 1965 only - Jun 1 0:00 1:00 D +Rule Cuba 1965 only - Sep 30 0:00 0 S +Rule Cuba 1966 only - May 29 0:00 1:00 D +Rule Cuba 1966 only - Oct 2 0:00 0 S +Rule Cuba 1967 only - Apr 8 0:00 1:00 D +Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S +Rule Cuba 1968 only - Apr 14 0:00 1:00 D +Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D +Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S +Rule Cuba 1972 1974 - Oct 8 0:00 0 S +Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S +Rule Cuba 1978 only - May 7 0:00 1:00 D +Rule Cuba 1978 1990 - Oct Sun>=8 0:00 0 S +Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D +Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D +Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D +Rule Cuba 1990 1997 - Apr Sun>=1 0:00 1:00 D +Rule Cuba 1991 1995 - Oct Sun>=8 0:00s 0 S +Rule Cuba 1996 only - Oct 6 0:00s 0 S +Rule Cuba 1997 only - Oct 12 0:00s 0 S +Rule Cuba 1998 1999 - Mar lastSun 0:00s 1:00 D +Rule Cuba 1998 2003 - Oct lastSun 0:00s 0 S +Rule Cuba 2000 2003 - Apr Sun>=1 0:00s 1:00 D +Rule Cuba 2004 only - Mar lastSun 0:00s 1:00 D +Rule Cuba 2006 2010 - Oct lastSun 0:00s 0 S +Rule Cuba 2007 only - Mar Sun>=8 0:00s 1:00 D +Rule Cuba 2008 only - Mar Sun>=15 0:00s 1:00 D +Rule Cuba 2009 2010 - Mar Sun>=8 0:00s 1:00 D +Rule Cuba 2011 only - Mar Sun>=15 0:00s 1:00 D +Rule Cuba 2011 only - Nov 13 0:00s 0 S +Rule Cuba 2012 only - Apr 1 0:00s 1:00 D +Rule Cuba 2012 max - Nov Sun>=1 0:00s 0 S +Rule Cuba 2013 max - Mar Sun>=8 0:00s 1:00 D + +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Havana -5:29:28 - LMT 1890 + -5:29:36 - HMT 1925 Jul 19 12:00 # Havana MT + -5:00 Cuba C%sT + +# Dominican Republic + +# From Steffen Thorsen (2000-10-30): +# Enrique Morales reported to me that the Dominican Republic has changed the +# time zone to Eastern Standard Time as of Sunday 29 at 2 am.... +# http://www.listin.com.do/antes/261000/republica/princi.html + +# From Paul Eggert (2000-12-04): +# That URL (2000-10-26, in Spanish) says they planned to use US-style DST. + +# From Rives McDow (2000-12-01): +# Dominican Republic changed its mind and presidential decree on Tuesday, +# November 28, 2000, with a new decree. On Sunday, December 3 at 1:00 AM the +# Dominican Republic will be reverting to 8 hours from the International Date +# Line, and will not be using DST in the foreseeable future. The reason they +# decided to use DST was to be in synch with Puerto Rico, who was also going +# to implement DST. When Puerto Rico didn't implement DST, the president +# decided to revert. + + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule DR 1966 only - Oct 30 0:00 1:00 EDT +Rule DR 1967 only - Feb 28 0:00 0 EST +Rule DR 1969 1973 - Oct lastSun 0:00 0:30 -0430 +Rule DR 1970 only - Feb 21 0:00 0 EST +Rule DR 1971 only - Jan 20 0:00 0 EST +Rule DR 1972 1974 - Jan 21 0:00 0 EST +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Santo_Domingo -4:39:36 - LMT 1890 + -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT + -5:00 DR %s 1974 Oct 27 + -4:00 - AST 2000 Oct 29 2:00 + -5:00 US E%sT 2000 Dec 3 1:00 + -4:00 - AST + +# El Salvador + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D +Rule Salv 1987 1988 - Sep lastSun 0:00 0 S +# There are too many San Salvadors elsewhere, so use America/El_Salvador +# instead of America/San_Salvador. +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador + -6:00 Salv C%sT + +# Guatemala +# +# From Gwillim Law (2006-04-22), after a heads-up from Oscar van Vlijmen: +# Diario Co Latino, at +# <http://www.diariocolatino.com/internacionales/detalles.asp?NewsID=8079>, +# says in an article dated 2006-04-19 that the Guatemalan government had +# decided on that date to advance official time by 60 minutes, to lessen the +# impact of the elevated cost of oil.... Daylight saving time will last from +# 2006-04-29 24:00 (Guatemalan standard time) to 2006-09-30 (time unspecified). +# From Paul Eggert (2006-06-22): +# The Ministry of Energy and Mines, press release CP-15/2006 +# (2006-04-19), says DST ends at 24:00. See +# http://www.sieca.org.gt/Sitio_publico/Energeticos/Doc/Medidas/Cambio_Horario_Nac_190406.pdf + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Guat 1973 only - Nov 25 0:00 1:00 D +Rule Guat 1974 only - Feb 24 0:00 0 S +Rule Guat 1983 only - May 21 0:00 1:00 D +Rule Guat 1983 only - Sep 22 0:00 0 S +Rule Guat 1991 only - Mar 23 0:00 1:00 D +Rule Guat 1991 only - Sep 7 0:00 0 S +Rule Guat 2006 only - Apr 30 0:00 1:00 D +Rule Guat 2006 only - Oct 1 0:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5 + -6:00 Guat C%sT + +# Haiti +# From Gwillim Law (2005-04-15): +# Risto O. Nykänen wrote me that Haiti is now on DST. +# I searched for confirmation, and I found a press release +# on the Web page of the Haitian Consulate in Chicago (2005-03-31), +# <http://www.haitianconsulate.org/time.doc>. Translated from French, it says: +# +# "The Prime Minister's Communication Office notifies the public in general +# and the press in particular that, following a decision of the Interior +# Ministry and the Territorial Collectivities [I suppose that means the +# provinces], Haiti will move to Eastern Daylight Time in the night from next +# Saturday the 2nd to Sunday the 3rd. +# +# "Consequently, the Prime Minister's Communication Office wishes to inform +# the population that the country's clocks will be set forward one hour +# starting at midnight. This provision will hold until the last Saturday in +# October 2005. +# +# "Port-au-Prince, March 31, 2005" +# +# From Steffen Thorsen (2006-04-04): +# I have been informed by users that Haiti observes DST this year like +# last year, so the current "only" rule for 2005 might be changed to a +# "max" rule or to last until 2006. (Who knows if they will observe DST +# next year or if they will extend their DST like US/Canada next year). +# +# I have found this article about it (in French): +# http://www.haitipressnetwork.com/news.cfm?articleID=7612 +# +# The reason seems to be an energy crisis. + +# From Stephen Colebourne (2007-02-22): +# Some IATA info: Haiti won't be having DST in 2007. + +# From Steffen Thorsen (2012-03-11): +# According to several news sources, Haiti will observe DST this year, +# apparently using the same start and end date as USA/Canada. +# So this means they have already changed their time. +# +# http://www.alterpresse.org/spip.php?article12510 +# http://radiovision2000haiti.net/home/?p=13253 +# +# From Arthur David Olson (2012-03-11): +# The alterpresse.org source seems to show a US-style leap from 2:00 a.m. to +# 3:00 a.m. rather than the traditional Haitian jump at midnight. +# Assume a US-style fall back as well. + +# From Steffen Thorsen (2013-03-10): +# It appears that Haiti is observing DST this year as well, same rules +# as US/Canada. They did it last year as well, and it looks like they +# are going to observe DST every year now... +# +# http://radiovision2000haiti.net/public/haiti-avis-changement-dheure-dimanche/ +# http://www.canalplushaiti.net/?p=6714 + +# From Steffen Thorsen (2016-03-12): +# Jean Antoine, editor of www.haiti-reference.com informed us that Haiti +# are not going on DST this year. Several other resources confirm this: ... +# https://www.radiotelevisioncaraibes.com/presse/heure_d_t_pas_de_changement_d_heure_pr_vu_pour_cet_ann_e.html +# https://www.vantbefinfo.com/changement-dheure-pas-pour-haiti/ +# http://news.anmwe.com/haiti-lheure-nationale-ne-sera-ni-avancee-ni-reculee-cette-annee/ + +# From Steffen Thorsen (2017-03-12): +# We have received 4 mails from different people telling that Haiti +# has started DST again today, and this source seems to confirm that, +# I have not been able to find a more authoritative source: +# https://www.haitilibre.com/en/news-20319-haiti-notices-time-change-in-haiti.html + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Haiti 1983 only - May 8 0:00 1:00 D +Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D +Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S +# Shanks & Pottenger say AT is 2:00, but IATA SSIM (1991/1997) says 1:00s. +# Go with IATA. +Rule Haiti 1988 1997 - Apr Sun>=1 1:00s 1:00 D +Rule Haiti 1988 1997 - Oct lastSun 1:00s 0 S +Rule Haiti 2005 2006 - Apr Sun>=1 0:00 1:00 D +Rule Haiti 2005 2006 - Oct lastSun 0:00 0 S +Rule Haiti 2012 2015 - Mar Sun>=8 2:00 1:00 D +Rule Haiti 2012 2015 - Nov Sun>=1 2:00 0 S +Rule Haiti 2017 max - Mar Sun>=8 2:00 1:00 D +Rule Haiti 2017 max - Nov Sun>=1 2:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Port-au-Prince -4:49:20 - LMT 1890 + -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT + -5:00 Haiti E%sT + +# Honduras +# Shanks & Pottenger say 1921 Jan 1; go with Whitman's more precise Apr 1. + +# From Paul Eggert (2006-05-05): +# worldtimezone.com reports a 2006-05-02 Spanish-language AP article +# saying Honduras will start using DST midnight Saturday, effective 4 +# months until September. La Tribuna reported today +# <http://www.latribuna.hn/99299.html> that Manuel Zelaya, the president +# of Honduras, refused to back down on this. + +# From Jesper Nørgaard Welen (2006-08-08): +# It seems that Honduras has returned from DST to standard time this Monday at +# 00:00 hours (prolonging Sunday to 25 hours duration). +# http://www.worldtimezone.com/dst_news/dst_news_honduras04.html + +# From Paul Eggert (2006-08-08): +# Also see Diario El Heraldo, The country returns to standard time (2006-08-08). +# http://www.elheraldo.hn/nota.php?nid=54941&sec=12 +# It mentions executive decree 18-2006. + +# From Steffen Thorsen (2006-08-17): +# Honduras will observe DST from 2007 to 2009, exact dates are not +# published, I have located this authoritative source: +# http://www.presidencia.gob.hn/noticia.aspx?nId=47 + +# From Steffen Thorsen (2007-03-30): +# http://www.laprensahn.com/pais_nota.php?id04962=7386 +# So it seems that Honduras will not enter DST this year.... + +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Hond 1987 1988 - May Sun>=1 0:00 1:00 D +Rule Hond 1987 1988 - Sep lastSun 0:00 0 S +Rule Hond 2006 only - May Sun>=1 0:00 1:00 D +Rule Hond 2006 only - Aug Mon>=1 0:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr + -6:00 Hond C%sT +# +# Great Swan I ceded by US to Honduras in 1972 + +# Jamaica +# Shanks & Pottenger give -5:07:12, but Milne records -5:07:10.41 from an +# unspecified official document, and says "This time is used throughout the +# island". Go with Milne. +# +# Shanks & Pottenger give April 28 for the 1974 spring-forward transition, but +# Lance Neita writes that Prime Minister Michael Manley decreed it January 5. +# Assume Neita meant Jan 6 02:00, the same as the US. Neita also writes that +# Manley's supporters associated this act with Manley's nickname "Joshua" +# (recall that in the Bible the sun stood still at Joshua's request), +# and with the Rod of Correction which Manley said he had received from +# Haile Selassie, Emperor of Ethiopia. See: +# Neita L. The politician in all of us. Jamaica Observer 2014-09-20 +# http://www.jamaicaobserver.com/columns/The-politician-in-all-of-us_17573647 +# +# Zone NAME STDOFF RULES FORMAT [UNTIL] + #STDOFF -5:07:10.41 +Zone America/Jamaica -5:07:10 - LMT 1890 # Kingston + -5:07:10 - KMT 1912 Feb # Kingston Mean Time + -5:00 - EST 1974 + -5:00 US E%sT 1984 + -5:00 - EST + +# Martinique +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France + -4:04:20 - FFMT 1911 May 1 # Fort-de-France MT + -4:00 - AST 1980 Apr 6 + -4:00 1:00 ADT 1980 Sep 28 + -4:00 - AST + +# Nicaragua +# +# This uses Shanks & Pottenger for times before 2005. +# +# From Steffen Thorsen (2005-04-12): +# I've got reports from 8 different people that Nicaragua just started +# DST on Sunday 2005-04-10, in order to save energy because of +# expensive petroleum. The exact end date for DST is not yet +# announced, only "September" but some sites also say "mid-September". +# Some background information is available on the President's official site: +# http://www.presidencia.gob.ni/Presidencia/Files_index/Secretaria/Notas%20de%20Prensa/Presidente/2005/ABRIL/Gobierno-de-nicaragua-adelanta-hora-oficial-06abril.htm +# The Decree, no 23-2005 is available here: +# http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2005/Decreto%2023-2005%20Se%20adelanta%20en%20una%20hora%20en%20todo%20el%20territorio%20nacional%20apartir%20de%20las%2024horas%20del%2009%20de%20Abril.pdf +# +# From Paul Eggert (2005-05-01): +# The decree doesn't say anything about daylight saving, but for now let's +# assume that it is daylight saving.... +# +# From Gwillim Law (2005-04-21): +# The Associated Press story on the time change, which can be found at +# http://www.lapalmainteractivo.com/guias/content/gen/ap/America_Latina/AMC_GEN_NICARAGUA_HORA.html +# and elsewhere, says (fifth paragraph, translated from Spanish): "The last +# time that a change of clocks was applied to save energy was in the year 2000 +# during the Arnoldo Alemán administration."... +# The northamerica file says that Nicaragua has been on UTC-6 continuously +# since December 1998. I wasn't able to find any details of Nicaraguan time +# changes in 2000. Perhaps a note could be added to the northamerica file, to +# the effect that we have indirect evidence that DST was observed in 2000. +# +# From Jesper Nørgaard Welen (2005-11-02): +# Nicaragua left DST the 2005-10-02 at 00:00 (local time). +# http://www.presidencia.gob.ni/presidencia/files_index/secretaria/comunicados/2005/septiembre/26septiembre-cambio-hora.htm +# (2005-09-26) +# +# From Jesper Nørgaard Welen (2006-05-05): +# http://www.elnuevodiario.com.ni/2006/05/01/nacionales/18410 +# (my informal translation) +# By order of the president of the republic, Enrique Bolaños, Nicaragua +# advanced by sixty minutes their official time, yesterday at 2 in the +# morning, and will stay that way until 30th of September. +# +# From Jesper Nørgaard Welen (2006-09-30): +# http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2006/D-063-2006P-PRN-Cambio-Hora.pdf +# My informal translation runs: +# The natural sun time is restored in all the national territory, in that the +# time is returned one hour at 01:00 am of October 1 of 2006. +# +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D +Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S +Rule Nic 2005 only - Apr 10 0:00 1:00 D +Rule Nic 2005 only - Oct Sun>=1 0:00 0 S +Rule Nic 2006 only - Apr 30 2:00 1:00 D +Rule Nic 2006 only - Oct Sun>=1 1:00 0 S +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Managua -5:45:08 - LMT 1890 + -5:45:12 - MMT 1934 Jun 23 # Managua Mean Time? + -6:00 - CST 1973 May + -5:00 - EST 1975 Feb 16 + -6:00 Nic C%sT 1992 Jan 1 4:00 + -5:00 - EST 1992 Sep 24 + -6:00 - CST 1993 + -5:00 - EST 1997 + -6:00 Nic C%sT + +# Cayman Is +# Panama +# +# Atikokan and Coral Harbour, Canada, match Panama since 1970. +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Panama -5:18:08 - LMT 1890 + -5:19:36 - CMT 1908 Apr 22 # Colón Mean Time + -5:00 - EST + +# Anguilla +# Antigua & Barbuda +# Aruba +# Caribbean Netherlands +# Curaçao +# Dominica +# Grenada +# Guadeloupe +# Montserrat +# Puerto Rico +# St Barthélemy +# St Kitts-Nevis +# Sint Maarten / St Martin +# St Lucia +# St Vincent & the Grenadines +# Trinidad & Tobago +# Virgin Is (UK & US) +# +# There are too many San Juans elsewhere, so we'll use 'Puerto_Rico'. +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan + -4:00 - AST 1942 May 3 + -4:00 US A%sT 1946 + -4:00 - AST + +# St Pierre and Miquelon +# There are too many St Pierres elsewhere, so we'll use 'Miquelon'. +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Miquelon -3:44:40 - LMT 1911 Jun 15 # St Pierre + -4:00 - AST 1980 May + -3:00 - -03 1987 + -3:00 Canada -03/-02 + +# Turks and Caicos +# +# From Chris Dunn in +# https://bugs.debian.org/415007 +# (2007-03-15): In the Turks & Caicos Islands (America/Grand_Turk) the +# daylight saving dates for time changes have been adjusted to match +# the recent U.S. change of dates. +# +# From Brian Inglis (2007-04-28): +# http://www.turksandcaicos.tc/calendar/index.htm [2007-04-26] +# there is an entry for Nov 4 "Daylight Savings Time Ends 2007" and three +# rows before that there is an out of date entry for Oct: +# "Eastern Standard Times Begins 2007 +# Clocks are set back one hour at 2:00 a.m. local Daylight Saving Time" +# indicating that the normal ET rules are followed. + +# From Paul Eggert (2014-08-19): +# The 2014-08-13 Cabinet meeting decided to stay on UT -04 year-round. See: +# http://tcweeklynews.com/daylight-savings-time-to-be-maintained-p5353-127.htm +# Model this as a switch from EST/EDT to AST ... +# From Chris Walton (2014-11-04): +# ... the TCI government appears to have delayed the switch to +# "permanent daylight saving time" by one year.... +# http://tcweeklynews.com/time-change-to-go-ahead-this-november-p5437-127.htm +# +# From the Turks & Caicos Cabinet (2017-07-20), heads-up from Steffen Thorsen: +# ... agreed to the reintroduction in TCI of Daylight Saving Time (DST) +# during the summer months and Standard Time, also known as Local +# Time, during the winter months with effect from April 2018 ... +# https://www.gov.uk/government/news/turks-and-caicos-post-cabinet-meeting-statement--3 +# From Paul Eggert (2017-08-26): +# The date of effect of the spring 2018 change appears to be March 11, +# which makes more sense. See: Hamilton D. Time change back +# by March 2018 for TCI. Magnetic Media. 2017-08-25. +# http://magneticmediatv.com/2017/08/time-change-back-by-march-2018-for-tci/ +# +# From P Chan (2020-11-27): +# Standard Time Declaration Order 2015 (L.N. 15/2015) +# http://online.fliphtml5.com/fizd/czin/#p=2 +# +# Standard Time Declaration Order 2017 (L.N. 31/2017) +# http://online.fliphtml5.com/fizd/dmcu/#p=2 +# +# From Tim Parenti (2020-12-05): +# Although L.N. 31/2017 reads that it "shall come into operation at 2:00 a.m. +# on 11th March 2018", a precise interpretation here poses some problems. The +# order states that "the standard time to be observed throughout the Turks and +# Caicos Islands shall be the same time zone as the Eastern United States of +# America" and further clarifies "[f]or the avoidance of doubt" that it +# "applies to the Eastern Standard Time as well as any changes thereto for +# Daylight Saving Time." However, as clocks in Turks and Caicos approached +# 02:00 -04, and thus the declared implementation time, it was still 01:00 EST +# (-05), as DST in the Eastern US would not start until an hour later. +# +# Since it is unlikely that those on the islands switched their clocks twice in +# the span of an hour, we assume instead that the adoption of EDT actually took +# effect once clocks in the Eastern US had sprung forward, from 03:00 -04. +# This discrepancy only affects the time zone abbreviation and DST flag for the +# intervening hour, not wall clock times, as -04 was maintained throughout. + +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone America/Grand_Turk -4:44:32 - LMT 1890 + #STDOFF -5:07:10.41 + -5:07:10 - KMT 1912 Feb # Kingston Mean Time + -5:00 - EST 1979 + -5:00 US E%sT 2015 Mar 8 2:00 + -4:00 - AST 2018 Mar 11 3:00 + -5:00 US E%sT + +# Local Variables: +# coding: utf-8 +# End: |