Historical U.S. census and vital records

91.9 million persons

Geography: Add Arizona, New Mexico, Oklahoma; Puerto Rico (first census 1899; then 1910 and decennially.)

Publications at the U.S. Census Bureau website  

105.7 million persons

Publications at the U.S. Census Bureau website  

122.7 million persons

Publications at the U.S. Census Bureau website  

131.7 million persons

http://1940census.archives.gov/

Publications at the U.S. Census Bureau website