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+# Incremental Sum (`incremental_sum`)
+
+This modules finds the incremental sum of a period, which `last value - first value`.
+
+The result may be positive (rising) or negative (falling) depending on the first and last values.
+
+## how to use
+
+Use it in alarms like this:
+
+```
+ alarm: my_alarm
+    on: my_chart
+lookup: incremental_sum -1m unaligned of my_dimension
+  warn: $this > 1000
+```
+
+`incremental_sum` does not change the units. For example, if the chart units is `requests/sec`, the result
+will be again expressed in the same units. 
+
+It can also be used in APIs and badges as `&group=incremental_sum` in the URL.
+
+## Examples
+
+Examining last 1 minute `successful` web server responses:
+
+- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=min&after=-60&label=min)
+- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=average&after=-60&label=average)
+- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=max&after=-60&label=max)
+- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=incremental_sum&after=-60&label=incremental+sum&value_color=orange)
+
+## References
+
+- none