Today, former President Jimmy Carter surpassed former President Herbert Hoover for longevity in retirement, having reached the 11,554th day after leaving the Presidency.
He has been retired for 31 years, seven and a half months, and has been an extremely active former President, much like Herbert Hoover was.
Both were constantly berated in retirement and seen as failures, because they lost re-election to Franklin D. Roosevelt and Ronald Reagan, often considered the two Presidents of the 20th century who have had the most impact on the nation in the past century!
Carter will be 88 on October 1, with only Gerald Ford and Ronald Reagan at 93, John Adams and Herbert Hoover at 90, and Harry Truman and George H. W. Bush at 88, having lived longer!
Carter seems to be in excellent health, and it would not be surprising if he manages to live long enough to surpass Gerald Ford in March 2018 as our longest lived President of the United States!