Huh, If you have 10 east pilots and 10 west pilots and the 10 east pilots retire, which 10 are left? In know this is a tough concept but,.....
Answere, shows why your data is wrong..... using your example, you have 20 pilots total, 10 east retired as did 4 West, the nest 20 on the Nic are all east, so you now have 14 east 6 West. This goes on until the top 517 are gone sometime in 2018 according to the lists DOB info, and you find that your blue vs red graphic is full of BS, as is your 10 year prediction.