David Cameron has been rated one of the worst prime ministers in modern history by political experts.
The Conservative came third from bottom in the table of post-war leaders but would have been classed as the biggest failure based on rankings for only his second term.
Mr Cameron fared worse than Labour's Gordon Brown, the premier he regularly mocked while opposition leader, in the survey of academics who specialise in politics and contemporary British history.
Nearly nine out of ten said the European Union referendum was his greatest failure, with one claiming it was the greatest defeat of any prime minister "since Lord North lost America".
Only Sir Anthony Eden, whose reputation was left in tatters by his handling of the Suez crisis, and Sir Alec Douglas-Home, who only lasted a year, were ranked lower than Mr Cameron in the list of 13 prime ministers who have served since 1945.
University of Leeds professor Kevin Theakston, who carried out the research, said: "For all his achievements as a successful coalition prime minister, David Cameron's reputation and place in history seems destined to be defined by Brexit and his calling and losing the referendum.
"Academic opinion, as reflected in our survey, is currently pretty damning. But reputations can wax and wane as subsequent events, the passage of time and new evidence change perspectives.
"Depending on how Brexit works out, future historians and political scientists may come to a different verdict on Mr Cameron's premiership and his place in the league table of prime ministers."
The survey, carried out with research company Woodnewton Associates, follows similar polls in 2004 and 2010.
Labour's Clement Attlee was again assessed as the most successful prime minister, scoring 8.5. He was followed by Margaret Thatcher on 7.2 and Tony Blair on 6.7.
Winston Churchill received only a 5.4 because the assessment is based on his 1950s government rather than his wartime leadership.
Mr Brown was rated 4.6 while Sir Alec Douglas-Home scored 3.8 and Sir Anthony came bottom on 2.4.
Mr Cameron scored 4 but when asked to rate his stints at No 10 separately he received 5.6 for the coalition years but just 2.1 for his time in No 10 since his 2015 election victory.
Prof Theakston said: "This would place him at the bottom of the league table - as a worse prime minster than Anthony Eden, long seen as the biggest post-war failure in Number 10."
Academics were also asked to rate the impact each of the last five prime ministers had on society, the economy, foreign policy and Britain's role in the world, their political party, and democracy.
Mr Cameron was the only one to receive a negative rating in each area.
The online survey was completed by 82 academics.