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Roll-Up Report type: Click the required report type - Epic Roll-Up, Sprint Roll-Up, Fix Version Roll-Up, Agile Board Roll-Up, Issue Type Roll-Up, and Custom Roll-Up to view the Roll-Up Report.
Configuration fields: Provides various configuration fields based on the chosen report type.
Columns: The Columns columns drop-down contains all the standard Jira Text fields, Date fields, and Numeric fields. You can select the required fields and click Done to add to the report result. The fields with a
symbol displays help text on mouseover. To remove a field from the report result, deselect the field from the Columns drop-down. 
Projects: The Projects drop-down list all the projects. By default, the Roll-Up Report report displays the result from all the projects. To view the report result for specific projects, select the required projects and click Done. The Projects drop-down gets prefixed with a filter icon to indicate that the report result is for specific projects selection.
Include Sub Tasks: To include the subtask for the chosen parent entity such as Epic, Sprint, Fix Version, Agile Board, Issue Type, and any Custom Jira field in the report result, select Include Sub Tasks.
Time display unit : - Time display unit provides the option to display time in Hours, Days, and Pretty unit.
Other configuration fields: Based on the selected report type, other configuration fields are displayed such as Epic Status, Sprints Sprint Status, Fix Versions, Boards, Issue types and Roll-Up Field.
Actions allow you to save selections for the report type, download the report, and refresh the report result.
Save Selections: Once you change your selections for report result, the 💾 (Save Selections) icon turns red. The red mark save icon indicates that the selections are not saved. To save the your selection configurations of report type for the next time you revisit the report type, refer to Save Roll-Up Report Reports Selections.
Export to excel: To download the result of Roll-Up Report type, click ⬇ (Export to excel). The report is downloaded in Excel format and can be viewed in downloads.
Refresh results: To refresh the report, click 🔁 (Refresh results).
Report result: Report result section displays the report for the chosen report type. Configuration fields can be added to the report as required. To expand the report view, click >. The expanded view displays the report at the issue-level with details. You can expand (>) and collapse (🔽) the view at the issue level as needed.
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To know the details of each report type, refer to the following pages.