The way I understand it increases based on their number of years in congress/Senate. I can't remember now where I saw the breakdown, but it's substantial.
I understand that. I'm saying that whether a Congressional figurehead or the President "retire" at 50 or 65, they're receiving benefits the moment they leave office. Truth be told, they're getting benefits even while in office. My understanding is they receive the benefits regardless of being in office or not, it just increases substantially as they age whether in office or not.