The cManager analysis reports have been enhanced to allow you to use advanced filtering to make reports more powerful and suitable for your reporting needs.
To show the Advanced Filter Editor, right click in the field area and click on "Show Filter Editor"
For full end-user documentation on the Filter Editor control, please see Advanced Filtering
A. Date Filtering - Closed Cases in the last 60 days
With this filter, this report will always pick up cases closed in the last 60 days from the current date, so you don't need to manually change the report dates
[Close] > ADDDAYS(TODAY(),-90 )