AMEX Charge: 12 Years of Backdating Worth AF?

[Wolf3]

For me, it would be 24 years of backdating ( but not my oldest).   It would raise my AAoA  from 5 to 6 years.   Not worth it to me.

[Leadberry]

I did the math, and the extra backdated account would only raise my AAoA by 0.5 years, not to mention that the effect would be even less pronounced as time passes.  Definitely not worth the AF.  Thanks to all who chimed in!

P.S. - To any who are interested, Amex did confirm that when I open my own card(s), my "member since" date will be the date I became an ACM (2001).