1940 IPUMS Research

The Integrated Public Use Microdata Series (IPUMS) is the world's largest population database, including individual-level microdata from the U.S. decennial censuses of 1790-2010. The 1940 IPUMS Research file includes the complete count U.S. census microdata from 1940. This microdata represents the fruition of longstanding collaborations between IPUMS and the nation's two largest genealogical organizations, Ancestry.com and FamilySearch, to leverage genealogical data for scientific purposes. This microdata collection is possible due to the donations of an unprecedented scale of digitized census data by both Ancestry.com and FamilySearch.

The complete count 1940 census microdata is available to researchers directly from the University of Minnesota. Researchers should select this data from ResearchDataGov only if they intend to use the files as part of a project in the Federal Statistical Research Data Centers.

The project review timeframes above do not apply to applications that request access to confidential data assets commingled with data that are either not owned, or are only co-owned, by the statistical agency(s) or unit(s) and require approval from third parties not subject to this policy (e.g., state and local government agencies).