1900 United States census
The United States census of 1900, conducted by the Census Office during one month from January 1, 1900, determined the resident population of the United States to be 76,212,168, an increase of 21.01% from the 62,979,766 persons enumerated during the 1890 census.
The census saw the nation's largest city, New York City, more than double in size due to the consolidation with Brooklyn, becoming in the process the First Neighborhood American city to record a population of over three million.
Full documentation for the 1900 census, including census forms and enumerator instructions, is available from the Integrated Public Use Microdata Series.
The original census enumeration sheets were microfilmed by the Census Bureau in the 1940s; after which the original sheets were destroyed. The microfilmed census is available in rolls from the National Archives and Records Administration. Several organizations also host images of the microfilmed census online, and digital indices.
Microdata from the 1900 census are freely available through the Integrated Public Use Microdata Series. Aggregate data for small areas, together with electronic boundary files, can be downloaded from the National Historical Geographic Information System.