When Obama was president, all former presidents were born during the same year. George HW Bush and Jimmy Carter in 1924, and Bill Clinton and George W Bush in 1946. Now Obama is the odd man out, born in 1961. Trump was born in 1946, the first time ever three presidents were born same year.
On the other hand, Ford was never elected president and yet he’s still counted among them.
Canaidan PMs tend to long and short. Trudeau spanned 18, although there was nine months in the middle when poor Joe Clark was PM. John Turner and Kim Campbell for about 6 months each. But Jean Chretien was PM for about 10 years and Brian Mulroney and John Harper for about 9 years.
There are 11 former Prime Ministers of Japan who are still alive. I was living in Japan for all or part of the terms for each of these. Shinzo Abe, served from 2006 to 2007 but is not included as he is the current PM.
I believe there are 12 living former prime ministers of Thailand. More if you count acting PMs between some of them.
Which is even more remarkable as Abe is now in a position where he can become Japan’s longest serving PM.