You can view information about when a Dynamic Report was last edited and last viewed.
From the SPC Reports, DMS Reports Advanced Reports or Mixed Reports tab on the Dynamic Reports screen, right-click a report and then click Report Properties. Alternately, you may highlight a report, click the File menu, and then click Report Properties.
This will display the properties for the report:
Last edited by - the user who last modified this report
Last edited - the date and time when this report was most recently edited
Last used - the date and time when this report was most recently viewed