Characteristics of incoming British prime ministers

By THE DATA TEAM

NEW residents of Number 10 Downing Street have become younger in the 71 years since Clement Attlee swept to power in 1945. Theresa May, Britain′s incoming prime minister, will buck the trend. Between Mr Attlee and James Callaghan in 1976, the average age of new holders of the highest office was a prudent 59; between Margaret Thatcher (1979) and David Cameron (2010) the average was a winsome 48. Mrs May, at 59, will be the oldest incoming prime minister since Mr Callaghan. Experience, measured by both parliamentary tenure and time spent as a minister or as leader of the opposition, has been broadly decreasing too, while the average parliamentary service of MPs (at least since 1979) shows no such trend. Before Mrs Thatcher, the average length of parliamentary experience was 26 years and ministerial experience was ten years. Since 1979, these averages have fallen to 16 and six years, respectively.

Mrs May, with the longest tenure as Home Secretary since 1892, may be disappointed to learn that ministerial experience is actually negatively correlated with the perceived quality of PMs (as rated by a 2010 University of Leeds survey of 106 academics). Perhaps Gordon Brown′s comment in 2008, that politicians have seven years in the limelight until the public tire of them, has something to do with this. Mrs May will hope to last longer than he did.