Overseas migration estimates are final up to September quarter 2019 and preliminary from December quarter 2019. See Overseas migration in paragraph 9 of the Methodology for further information.

This time series is based on the '12/16 month rule' methodology and provides data from 2004 onwards. It has been used in calculating Australia's official estimated resident population (ERP) since September quarter 2006. NOM estimates from September quarter 2011 onward have been produced based on improved methods - see the: Information Paper: Improvements to the Estimation of Net Overseas Migration (cat. no. 3412.0.55.004). For further information, see paragraphs 11 to 37 of the Methodology.

To confidentialise, estimates in this data cube have been rounded to the nearest 10. As a result, sums of the components may not add exactly to totals. Rounded figures and unrounded figures should not be assumed to be accurate to the last digit shown. Analysis featured in the publication is based on unrounded data. Calculations made on rounded data may differ to those published.

The visa category information in this data cube represents the number of visas based on the visa type at the time of a traveller's specific movement. It is this specific movement that has been used to calculate NOM. Therefore, the number of visas in this data cube should not be confused with information on the number of visas granted by the Department of Home Affairs.

Over time, new visas created by Home Affairs are added to the visa hierarchy while the use of other visas may expire. Care should be taken in the analysis of overseas migration by visa over time.