FILE - In this April 2, 1940 file photo, William L. Austin, director of the U.S. Census Bureau, right, helps President Franklin D. Roosevelt fill out the large form at the White House in Washington. Veiled in secrecy for 72 years because of privacy protections, the 1940 U.S. Census is the first historical federal decennial survey to be made available on the Internet initially rather than on microfilm. (AP Photo)
The 1940 census records were released Apr. 2, with more than 21 million people alive in the U.S. and Puerto Rico.