ICPSR archives and disseminates census data acquired from the United States Census Bureau as well as files prepared by ICPSR and other principal investigators. Both microdata and aggregate data constitute ICPSR's census holdings. The microdata comprise individual responses to census questions while the aggregate data contain tabulations of the individual responses at various aggregate levels of observation such as states, counties, places, and census tracts.
These are public-use samples randomly selected from all of data collected by a census. ICPSR has microdata from the censuses of 2000, 1990, 1980, 1970, 1960, 1950, 1940, and some earlier censuses, with sampling fractions ranging from 10 to 0.01 percent.
The data files are typically hierarchical with separate household and person records. Common household variables include group quarters status, farm status, ownership of home, vacancy status, kitchen or cooking facilities, plumbing facilities, number of housing units in structure, number of rooms in unit, age of structure, and telephone availability.
Common person variables include age, sex, race, Hispanic status, relation to household head, marital status, place of birth, citizenship status, five-year migration status, school attendance, educational attainment, labor force status, employment status, occupation, industry, work disability, veteran status, and income.
ICPSR has extensive tabulations for the 1970-2000 decennial censuses: population size by sex, age, race, Hispanic origin, education status, employment status, occupation, and industry; median income, rent, and housing unit value; and tabulations of other population and housing characteristics. These tabulations are presented at many levels of observation including regions, states, counties, metropolitan areas, places, county subdivisions, census tracts/block numbering areas, block groups and blocks.
For the 1940-1960 decennial censuses, we have a limited number of tabulations for states, counties, cities, and census tracts, but for the 1790-1930 censuses only for states and counties.
September 13, 2010