Abstract: | "The 1990 population and housing census was the first one in Finland to be conducted entirely on the basis of registers, without any questionnaires. The Finnish population census system draws on the basic administrative registers of the society giving data on the population census target units and the links between them. These units comprise individuals, families, households, buildings, dwellings, enterprises and establishments. Transferring from one data collection method to another inevitably causes some kind of break in the time series. Because of these breaks it was decided in Statistics Finland to carry out an extensive evaluation study to analyse the differences between questionnaire-based and register-based census data." |