Data from the Central Register of Residents (ZMR) about main residence registrations has been forwarded quarterly to Statistics Austria since 2002. 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:
Annual average = (population on 1 January + 2x 1 April + 2x 1 July + 2x 1 October + 1 January of the following year) divided by 8.
For the time being, only data free of charge are being provided, for more detailed information please look at the respective database!