By the time the Labor Government was elected in December 1972 there were only about 120 Australian troops in Vietnam - as training officers with the Australian Army Training Team Vietnam (AATTV).
This can be seen in the advice given to the Australian government by its Ambassador to Washington:
The decision to scale back Australia's combat contribution was made in 1970, and all Australian combat troops had been returned to Australia well before December 1972.
Thousands of Brisbane residents turned out on 13 November 1970 to welcome home troops from 8RAR, the first Australian battalion to be withdrawn from Vietnam without being replaced.
(Photo from Queensland Newspapers; as reproduced in Peter Edwards, A Nation at War, Allen & Unwin, Sydney, 1997)