In this March 30, 2012, photo, Verla Morris, who will turn 100 later this year, goes through some of her family census data from the 19th and 20th centuries at her local residential senior center in Chandler, Ariz. When the 1940 census records are released Monday, April 2, Morris will see her own name and details about her life in the records being released after 72 years of confidentiality expires, allowing her to find out more about her family tree. (AP Photo/Ross D. Franklin)
The 1940 census records were released Apr. 2, with more than 21 million people alive in the U.S. and Puerto Rico.