Why would we have to give up a lot more to raise the cap? It would cost them money?

What kind of bonanza did they get when the retirement age was raised to 65? So if people are retiring at an average age (I heard 64 approximately) instead of what it was before (59ish, I'm guessing), that's five extra years they're not paying it, for every pilot. So what happened to that five years per pilot average extra pension that is unpaid? Where is that money?