Data.census.gov is the official repository for U.S. Census data on population and housing. This site replaces American FactFinder. Both aggregated and microdata are available here. Terms which may be helpful: "foreign born", "place of birth", "ancestry".
A compendium of tables that provides data on foreign nationals who, during a fiscal year, were granted lawful permanent residence (i.e., admitted as immigrants or became legal permanent residents), were admitted into the United States on a temporary basis (e.g., tourists, students, or workers), applied for asylum or refugee status, or were naturalized.
The Center for Immigration Studies is an independent, non-partisan, non-profit, research organization with a mission of providing immigration policymakers, the academic community, news media, and concerned citizens with reliable information about the social, economic, environmental, security, and fiscal consequences of legal and illegal immigration into the United States.
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