vote in support of the constitutional law, whereas a "Yes" in a popular referendum is a vote for abolishing the law. Also unlike popular referendums, constitutional referendums are not subject to a quorum, meaning they are valid regardless of the turnout. Only three constitutional referendums have ever been held in Italy: in 2001 (in which the constitutional law was approved), in 2006, and in 2016 (in which they were rejected). Ad hoc referendums Before the adoption of the Constitution of 1948, a unique referendum (called referendum on the institutional form of the State or institutional referendum in Italian) was held on 2 June 1946, Italians were asked to vote on the future form of government of Italy: retain the monarchy or become a republic. The republic vote won 54.3% to 45.7%. A special advisory referendum was held in 1989, on the question of transforming the European Communities into a European Union and of allowing the European Parliament to draft a European Constitution. This referendum was made possible by Constitutional Law no. 2 of 3 April 1989, which specifically provided for this referendum to be held. List of referendums Overall, Italians have been called on to decide on 72 national referendums: 67 popular referendums, 3 constitutional referendums, and the 2 ad hoc referendums described above. They approved 25 of them, rejected 18, and 28 were declared invalid because of low turnout. Referendum on the institutional form of the State 1946 Italian institutional referendum - retaining the monarchy of the House of Savoy or establishing a republic - republic victory. Popular referendums 1974 Italian referendum - abrogation of divorce - rejected 1978 Italian referendums - 2 questions: abrogation of public financing of political parties and of the act that strengthened law enforcement and improved public order reducing civil rights - all rejected 1981 Italian referendums - 5 questions: 2 about abortion (one for increasing and the other for reducing possibilities) and 3 about abrogation of life sentence, of restrictive rules on public order emergency of the 70s and of ability to possess firearms - all rejected 1985 Italian wage referendum - abrogation of cuts on the sliding wage scale - rejected 1987 Italian nuclear power referendum - 5 questions: abrogation of possibilities for Enel to build nuclear power plants abroad, of government grants to municipalities and provinces that host nuclear power plants, of opportunity for the government to build nuclear power plants