Track SLA breaches per team and/or per assignee with Performance Objectives: Charts for Jira app.
In this article you will find several approaches to track and display SLA Breaches (Breached vs Met report) on your Jira Service Management dashboard, choose the one that will fit your purpose best or configure them all and get this rich data visualization:

In the following examples we are using ‘Time to resolution’ metric, you can use any other SLA Metric you track in your JSM instance, e.g., ‘Time to first response’, ‘Time of comment’, etc.
Display SLA breach % of all issues per assignee
Employ the ‘Performance Objectives’ Dashboard gadget for streamlined setup. The chart visualization is simple to configure while offering comprehensive insights.

Please find here the recording with the configuration steps (time to watch 1 min.):
2. Set a target for breaches per assignee and track it as a KPI, using the ‘Performance Objectives’ dashboard gadget:

If you want to visualize how each team member is performing against a target, please follow the next configuration in which the target is set using ‘% Change’ section. It calculates % of achievement per assignee based on their individual number of issues (time to watch 1:21 min.):
If you want to dig deeper into your data, you may stack breaches by ‘issue type’ or ‘priority’ or any other supported field in the ‘Display settings’ and choose ‘Metric value’ for the y-Axis scale. You may also choose to see the result on top of the x-Axis as number achieved, not as %:

Here is the visualization with the above settings:

3. Set and track target for the whole team.
If you want to measure and track your whole team’s performance, please use the following configuration (video is 01:40 min.). Displaying data by ‘Issue Type’ or ‘Priority’ will enrich the chart with more details that can help your analysis:
More information about how to configure SLA Metrics using Performance Objectives app, please check the SLA Metrics article.
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