Metrics Idea: Average age of KSATs and stale KSATs (display change/report)

Scenario: I want to know the average age of KSATs and see if a KSAT has not been updated in a given amount of time.

Given a KSAT item or the entire MTTL

Then I want to see the average age of KSAT items in the MTTL

And I want to see if a KSAT has not been updated recently