Generate engineer report for average ticket close time

We are running RT 4.0.2 and need the availability to generate, on a per user / engineer basis, a report which will give the average time from ticket creation to ticket resolution.
I found this perl script:
The script there would probably serve the purpose well for what we need internally, except I am unsure where this was intended to run from. I would like to be able to create a link for each helpdesk user to see this type of information so that they can track their goals and work to cut down on ticket time. Most of our helpdesk does not use the ‘TimeWorked’ field, and even if so, that wouldn’t be a good representation of a ticket’s life span.

I apologize if this has been asked previously, but a search on my mail didn’t return anything promising. I would greatly appreciate any assistance.