That's to go from 14 to 16.

Anyhow, I know it's pointless to talk about this here on hnews, because the smug crowd that's read one or two articles on war is boring or such drown everything out, but I've seen this issue discussed by actual military aviators at length, and they were overwhelmingly of the opinion this F-15EX buy is a bad idea, and basically just a pork politics attempt for Boeing to pull some more cash their way.