STATE DISTRIBUTION OF NET OVERSEAS MIGRATION
The ABS is currently reviewing the methodology used to determine the Net Overseas Migration (NOM) figures which are used to calculate the Estimated Resident Population (ERP). The preliminary ERP figures (available approximately 6 months after the reference quarter) are used to determine important state funding decisions. However these often differ substantially from the revised figures (available 15 months after the end of each financial year).
Analytical Services Branch is currently working with Statistical Services Branch and the Demography section on a project to develop new methodology to distribute NOM between states. We are looking at developing methodology to improve the revised figures as well as methods to ensure the preliminary figures are more accurate (and so require less revision).
Of particular interest are travellers who category jump. That is, passengers whose initial categories (such as intended state and period of stay) differ from their eventual categories. When a traveller changes from being short term (less than 12 months) to long term they must be included in the ERP. Similarly, when they change from being long term to short term, they must be removed from ERP. This is taken into account through the migration adjustment.
This project is considering methods to more accurately estimate the preliminary migration adjustment, including a complex modelling approach and a simpler approach based on propensities. The visa category (or reason for travel) and country of citizenship as well as the quarter and the year are all being considered as useful explanatory variables.
For further information, please contact, Lucy Snowball on (02) 6252 7039.