The Australian Bureau of Statistics reported in 2005 that there were "13.2 million motor vehicles, including motor cycles, registered in Australia at 31 March 2003."
Year Book Australia, 2005. (2004, September). Australian Bureau of Statistics. Retrieved April 8, 2008 from http://www.abs.gov.au/Ausstats/abs@.nsf/94713ad445ff1425ca25682000192af2/22e7da19382d4bb2ca256f7200833044!OpenDocument.