The UK will have seven living ex-prime ministers for the first time in modern history when Liz Truss stands down.
She will join Boris Johnson, Theresa May, David Cameron, Gordon Brown, Sir Tony Blair and Sir John Major in what has become a fast-expanding group of former PMs.
The number of surviving ex-prime ministers has more than doubled in the past 15 years.
When Mr Brown became PM in 2007, only three of his predecessors were still alive: Sir Tony, Sir John and Baroness Margaret Thatcher.
The increase reflects both the rapid turnover of prime ministers in recent years and the age of those who have held the office.
Of the soon-to-be seven living ex-PMs, three are still under 60: Mr Johnson, aged 58; Mr Cameron, 56; and Ms Truss, 47.
Two are still below 70: Sir Tony (69) and Mrs May (66).
Mr Brown is 71 and Sir John is 79.
With the next general election due no later than January 2025, a Conservative defeat at the polls could see this group grow even further, from seven to eight.