The figures showing the size and structure of population are derived from decennial population censuses and from additional information on population balances and changes. The latter is obtained from processing statistical reports on marriages, divorces, births, deaths and migration, which are provided by Population Register. All of the state indicators reflect final results of the Population and Housing Census 2001. The figures on abortions are supplied to the Czech Statistical Office by the Institute of Health Information and Statistics of the CR. Data on numbers of foreigners with residence permit are taken over from the Directorate of Alien Police and from Asylum and Migration Policies Department of Ministry of the Interior the Czech Republic.