The youngest living former prime minister is Jacinda Ardern, born 26 July 1980 (aged 44 years, 203 days).
The prime minister with the shortest retirement is Joseph Ward, who died on 8 July 1930, 41 days after he left office on 28 May 1930.
Jim Bolger has held this distinction since Bill Rowling's death on 31 October 1995 a record 29 years, 106 days so far.
Robert Stout became the oldest living prime minister when John Hall died in 1907 and remained so until his death in 1930, for 23 years and 24 days.
Sidney Holland ceased to be the oldest living prime minister when Walter Nash was appointed.