The poster boy for off-the-rails, disastrous optimism is Neville Chamberlain, the British prime minister who met with Hitler in 1938 and handed him a big chunk of Czechoslovakia in exchange for the Fuhrer's word.

CNN: Is optimism really good for you?

In 1937, in Britain, Neville Chamberlain took over as prime minister at the head of a coalition government following Stanley Baldwin's retirement.

CNN: Wednesday,

Of the 20 prime ministers in the list, Neville Chamberlain and Sir Anthony Eden both scored zero - in Chamberlain's case because he "utterly failed in his principal objective of averting war".

BBC: Margaret Thatcher ruled from 1979 to 1990