Demographic data refer to the Decennial Census and other surveys of individuals and households administered by the Census Bureau. Compared to their public use counterparts, the internal data files include more detailed geographic information, generally to the block level for the Decennial Census and census-tract level for surveys, as well as less restrictive top-coding. The following table lists person and household based data, the frequency of data collection, the unit of enumeration, the years of data available at CES, and the sponsoring federal agency. Access to these data will only be granted to qualified researchers on approved projects with authorization to use specific data sets. All researcher access to restricted–use data occurs at one of the secure Federal Statistical Research Data Centers.

Some Census Bureau data collections are sponsored in whole or in part by other federal agencies. Sponsorship of data collections may also change over time. External research projects using these data may require permission of the sponsoring agency.

* The National Longitudinal Mortality Study (NLMS) is a unique research database based on a random sample of the non-institutionalized population of the United States. It consists of U.S. Census Bureau data from Current Population Surveys, Annual Social and Economic Supplements and a subset of the 1980 Census combined with death certificate information to identify mortality status and cause of death. The cohorts begin at various dates from 1973 through 1998 matched to death records dating through 1998.