Australia made voting compulsory in 1924, and turnout jumped above 90%

Worried by turnout of under 60% at the 1922 federal election, Australia's parliament made voting compulsory in 1924. At the next election turnout leapt to around 91%, and it has stayed high ever since, with small fines for anyone without a valid excuse. Supporters say it makes parliament reflect everyone; critics say a duty to vote sits uneasily with a free choice.

— Wikipedia contributors, Electoral system of Australia — Commonwealth Electoral Act 1924