Probably a few different threads I could put this in, but in case you're wondering when someone born in 1951 should start drawing on social security, and you also know their exact age when they'll die, here you go:
Formulas derived from info found
here. This plan maximizes the total payout.
62 is the earliest you can retire; retiring at 66 is "full" benefits; anything earlier than that and you get a reduction in payout per month. Anything later than that and you get a bonus per month, up until you're 70, at which point the bonuses cap out. But whenever you decide to retire locks in your pay rate.
So unless I screwed up my formulas somewhere, that funny lookin discontinuity at y = 66 means that the penalty / bonus system makes 66 the only age at which it's never the right time to retire, no matter when you die :-P