You can find historical data online in sources such as yearbooks from the Australian Bureau of Statistics (ABS).
Check the ABS Historical Statistics gateway page
Historical NZ yearbooks are another great source of detailed Australian historical statistics (originally collected to provide comparative data between the two countries)
The ABS - Find Historical Publications catalogues have tips on identifying other useful older ABS publications. Most of these are held in hardcopy in the UOW Library, with many older ABS publications held in the ABS Collection (Level 2 Compactus). Not all these titles are listed in the Library Catalogue. If you are trying to find a specific publication ask Library Staff for help with using this collection.
The Australian Bureau of Statistics: Census Data website contains data for the 2011, 2006 Census and 2001 Census, as well as selected data from the 1996 Census. Data from the most recent 2016 Census will be added progressively during 2017. Census data provides information on number of people in an area, their age, housing costs, average weekly incomes, industry of employment, religion etc.
Quick access to NSW Suburb level Census Data is available from the Quickstats website.
The Australian Bureau of Statistics: Historical Census Data website contains selected Commonwealth census data from 1911- 2006.
The Australian Historical and Colonial Census Data Archive contains selected Colonial census reports from 1833-1901.
In addition, the UOW Library holds a wide range of data from earlier Australian census in CD ROM, print and/or microfiche format. If you can't find the data you need online then please contact Library staff for assistance with these additional hardcopy sources.