@Anonymous
I don't believe I've seen this myself even though my AAoA (according to CK, anyway) is 2 years 8 months.
CK's calculation of AAoA is worthless, as it only looks at open accounts, not open and closed accounts. FICO scoring considers both, as does VS 3.0 actually, but CK's front end fluff software for whatever reason only gives you an average based on your open accounts. You can definitely ignore that 2 years 8 months.