There have been 8 successful constitutional referendums in Australia. Here is a list of the successful referendums and their outcomes:

1. 1906 - Senate Elections: To change the start date for senators terms, pushing them back six months so federal elections for both the Senate and House of Representatives could be held at the same time. Passed with all states and 82.65% of voters saying Yes.
2. 1910 - Navigation: To give the Commonwealth the power to make laws for the peace, order, and good government of navigation and shipping. Passed with 55.08% of voters saying Yes.
3. 1946 - Social Services: To allow the Commonwealth the power to legislate on a wide range of social services. Passed with 54.39% of voters saying Yes.
4. 1967 - Aboriginal People: To give the Federal Government the power to enact laws for Aboriginal people. To allow Aboriginal people to be counted in the Federal and State Census. Passed with 90.77% of voters saying Yes.
5. 1977 - Territorial Rights: Allowing electors in the Territories to vote in Constitutional referendums and have their vote count towards the national majority. Passed with 77.72% of voters saying Yes.
6. 1977 - Senate Casual Vacancies: To change the way casual vacancies in the Senate are filled. Passed with 64.98% of voters saying Yes.
7. 1977 - Commonwealth Grants: To give the Federal Government unrestricted power to take over State Government debts. Passed with 62.24% of voters saying Yes.
8. 1999 - Republic: To establish the Commonwealth of Australia as a republic with the Queen and Governor-General being replaced by a President appointed by a two-thirds majority of the members of the Commonwealth Parliament. Passed in the Australian Capital Territory and the Northern Territory, but failed nationally with 45.13% of voters saying Yes.

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