Forum Discussion
Create a measure/calculated field
This is the classic "Events in Progress" Problem I dealt with just a few weeks ago.
http://blog.crossjoin.co.uk/2011/11/10/solving-the-events-in-progress-problem-in-dax-v2-0/
The only way I was able to solve it was to have a calc cloumn that has the "Days Open" for each ticket. Then you can filter by category. Right now you are calculating average time open, which is nice to know, but not what you're looking for in this measure. Alternatively, you could make something like : overdue = if (days open > <target number>, 1,0) and do a countif based on category && overdue divided by countif category.
Hopefully that makes sense, still first cup of coffee.
Responsive ResidentYou can join benchmark table by category tier and than create a calculated measure that divides your benchmark value by row count to make it a static number.