How to calculate age of a work item in RTC
One answer
Your best bet will be creating an "aging report", as discussed here.
https://jazz.net/forum/questions/211621/how-can-i-report-on-the-age-of-defects-in-a-particular-state-in-my-workflow
If you want the "age" to be displayed in the work item editor for viewing only, I don't think it is achievable. A similar topic is discussed here.
https://jazz.net/forum/questions/222081/ibm-rtc-6-wi-age-calculation-update-automatically-no-dependency
https://jazz.net/forum/questions/211621/how-can-i-report-on-the-age-of-defects-in-a-particular-state-in-my-workflow
If you want the "age" to be displayed in the work item editor for viewing only, I don't think it is achievable. A similar topic is discussed here.
https://jazz.net/forum/questions/222081/ibm-rtc-6-wi-age-calculation-update-automatically-no-dependency