Currently my Average Age according to MyFico Equifax report is 9 years with my oldest account being 29 years 4 months. Now, when I do the calculation I come up with an AAoA of 9.3 or roughly 9 years 4 months.
Here is the problem/decision I am faced with: I have an account (former authorized user) with an age of 14 years 6 months. Unfortunately, it has 2 x 30 days late in 2006, 1 x 90 day late in 2006, and 2 x 30 days late in 2007. I have the opportunity to have it completely erased from my credit report.
Is it worth it? By my calculations the Average Age of my accounts would then be 9.05 which is essentially 9 years. Just to let you know: Total months for all accounts =1912; 17 trade lines reporting. So this would knock my total months down to 1738 and the number of trade lines would be 16...
Help... 
