Looking for the actual questions asked for a particular census, check here.
1850-2000 (IPUMS, University of Minnesota)
From the Minnesota Population Center (MPC) at the University of Minnesota, the actual questions from each of the previous censuses.
2000 Census (U. S. Census Bureau)
2010 Census (U. S. Census Bureau)
The questionnaires, both short and long forms, from the Census Bureau.
Explanatory texts from the Census Bureau on how they classify race and ethnicity. This is the first census where people could list multiple answers for race and ethnicity.
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