#  How to find the fluctuation of a metric ???

**URL:** <https://discuss.prometheus.io/t/how-to-find-the-fluctuation-of-a-metric/1407>\
**Category:** PromQL\
**Created:** [January 21, 2023, 5:39pm UTC](https://discuss.prometheus.io/t/how-to-find-the-fluctuation-of-a-metric/1407 "2023-01-21T17:39:40Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![athamour1](https://dub1.discourse-cdn.com/flex017/user_avatar/discuss.prometheus.io/athamour1/32/606_2.png) [@athamour1](https://discuss.prometheus.io/u/athamour1)\
**Post date:** [January 21, 2023, 5:39pm UTC](https://discuss.prometheus.io/t/how-to-find-the-fluctuation-of-a-metric/1407/1 "2023-01-21T17:39:40Z")

</div>

Hello, i am using prometheus and grafana to visualize data from a jenkins instance. I am using Jenkins metrics and prometheus metrics plugins to extract metrics for Prometheus, i have created a basic Grafana dashboard for instant metrics and some graphs and right now i need to create a promql query to extract the fluctuation from the last time the metric changes for the build time of a Jenkins job. I found out about `changes()` and `rate()` promql function but i don’t get the result i am waiting.

The last query that i used was: `changes(default_jenkins_builds_last_build_duration_milliseconds{jenkins_job="$project"}[1m])`  
where the variable `$project` let me select the job that i need to investigate in Grafana.

is that the right approach ???  
do you have any alternative idea ???