Cleaning up mentoring report to eliminate outdated mentor/mentee information

When I run the Mentoring Report, I see all the mentees that a mentor has had over the years.  Is there a way to "clean up" the report to show just active mentor/mentee activity?  For example, the report shows me with 5 mentees but 4 of these are no longer active.  When I read the instructions there was no reference to how to eliminate old data.  Thanks

Gerry Laures, 4868