most living Presidents

On what date were the most future, current, and former President living? My WAG is the day before a death or after a birth.

Being that six US presidents are alive today, the most ever, I would guess it would have been on Clinton’s birthday, 8/19/46, on which 12 past, present and future Chief Executives were living:

Past- Herbert Hoover (died 1964)
Present- Truman (died 1972)
Future- Eisenhower (died 1969), Kennedy (died 1963), Johnson (died 1973), Nixon (died 1994), Ford, Carter, Reagan, Bush Sr., Clinton and G.W. Bush (was a month old).

If my data and count is correct, I believe there were 18 past, current and future presidents live on July 3, 1826. The next day John Adams and Thomas Jefferson both died. I don’t know if this is the high point.

What year do we cut off future presidents – are we going to have any more born before 1940?

aahala seems correct. I though, modern times equals longer lifespans, and counted from the end down. But given the age most are elected at, starting at the beginning and counting up yields more.