The size of the poll on Saturday was a significant increase on the previous Nice turnout, which, at under 35 per cent, was the lowest ever on a European issue.
However, Saturday's vote on Nice fell far short of the last two EU votes. In 1992 the turnout for the Maastrich Treaty was 57.3 per cent. In 1998 the turnout for the Amsterdam Treaty was 56 per cent, boosted by the fact that it took place alongside the vote on the Belfast Agreement.
The referendum on the issue paving the way for the Maastricht, Amsterdam and Nice Treaties, the Single European Act, attracted only 44.1 per cent of registered voters when it was voted on in 1987.
This vote was only made possible by a Supreme Court ruling, in a case taken by the late Raymond Crotty, that referendums were necessary on EU Treaties. Without that, the only referendum to have been held on Europe would have been the 1972 decision on EEC membership, where there was a 70.9 poll, and an overwhelming 58.4 per cent of the total electorate voted Yes.