Since 2002, Statistics Austria has been receiving quarterly data of main residence registrations from the Central Register of Residents (ZMR). These data are used for maintaining a statistical population register using demographic concepts for producing consistent figures on population stock, population change and demographic events for all territorial units (LAU, NUTS). There is no further need to estimate annual population figures as it was done before 2002.
The annual average population is calculated as the arithmetic mean of quarterly figures applying the formula:
© STATISTICS AUSTRIA, Last Changed 12.02.2020