Three Prime Ministers have died in office – Joseph Lyons (1939), John Curtin (1945) and Harold Holt (1967) – and Robert Menzies resigned as Prime Minister in 1941. In each of these cases the Deputy Prime Minister (an unofficial office at the time) became an interim Prime Minister, pending an election of a new leader of the government party. In none of these cases was the interim Prime Minister successful at the subsequent election.