What I don't understand is how to interpret these retirement numbers and their relationship to recent hiring.

I'm looking to get hired early in 2018. Using APC numbers from 2018 to 2032, DAL's mandatory retirement total is 8,888. AA's is 11,159, which is higher both in absolute terms and as a % of pilots. On top of that, AA has not ramped up hiring yet, while DAL has added thousands (~4000?) in just the last few years.

Why have these two carriers approached this so differently? And the practical question for those starting their airline career--given that DAL appears to have tried to get ahead of the retirements, is a DAL new hire looking at big slowing in hiring ("only" a few thousand in 15 years) and therefore less movement, while an AA new hire will benefit from a lengthy sustained hiring boom?

The answer seems to be an obvious yes, but it's common to see people talk about the AA retirements... But rare to hear anyone warning against going to DAL due to upcoming stagnation. Am I missing something?