The following reports help you monitor and analyze work done for each ticket, by each assignee, in each ticket status. The reports are available in the Reports section for your Jira project
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The Assignee History Statistics report displays time spent on the project issues by each user.
The Assignee History Statistics helps you track how long each ticket assignee was working on the project tickets. To filter out data and display information that you need, you can specify the necessary options on the report configuration page. For example, you are interested in statistics during a specific period of time, you can select this timeframe in the configuration.
The report shows ticket history data grouped by assignees.
Issue History Statistics
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The report shows statistics grouped by tickets in the project.