The Census Bureau in 1940 conducted a survey of the nation's 33 million homes and 7 million farms. On April 2, the 72 years of confidentiality expired, and the National Archives website buckled under the load as the 1940 census records were released and 1.9 million users hit the archives servers in the first four hours the data went public. At one point, the Archives said, its computers were receiving 100,000 requests per second. The data, available via the Census bureau's website, comprises more than 3.8 million digital images of census schedules, maps and other sociological minutiae. The 1940 census was the first Census that looked deeper into the details of much of American life.