Censuses provide population numbers, household or family size and composition, and information on sex and age distribution. They often include other demographic, economic and health-related topics as well. The 1981 Spain de jure and de facto census collected data through self-enumeration on the subjects of housing, household demographics, employment, education, migration, and fertility. There were two questionnaires for private and collective dwellings. The census day was March 1, 1981. A 5% differentially weighted sample of dwellings from the census (2,084,221 individuals) is available through IPUMS International at the University of Minnesota.