04/02/2012 02:00 pm ET

1940 Census Records Released Online; U.S. Data On 132 Million Americans Unveiled After 72 Years

Don Drapers beware, the truth is now out there. The U.S. Census bureau released the 1940 census data of 132 million Americans at 8:30 a.m. ET this morning giving historians, genealogists, and the general public a long awaited glimpse into post-Depression and pre-World War II life.

While the aggregate data of censuses is generally more readily available, full records are never released until a significant amount of time has passed.

"In 1952, the director of the Census Bureau and the National Archivist agreed that keeping census records private for 72 years balanced public release of federal records with the tradition of confidentiality," the Census Bureau's Vicki Glasier explained to NPR.

At the time, the department believed that 72 years would be long enough that most of those surveyed wouldn't still be alive when the records were released. But according to the Associated Press, 21 million Americans surveyed in 1940 are still alive today.

The impact of the release may not be beneficial for all.

From the AP:

Jay Stanley, a senior policy analyst at the ACLU, said harm could come from combining the rich 1940 census data with other information.

"Computer technology today allows you to take information from different sources and combine it into a very high resolution image of somebody's life," he said. "Each particular piece of information might just be one pixel. But when brought together, they become very intrusive."

According to the official census site, the trove of historic census data contains 3.8 million images, scanned from over 4,000 rolls of microfilm.

CBS has reported that a team of researchers, working in conjunction with 100,000 volunteers, will comb through the data in an attempt to make it indexable and searchable by name.

But what has researchers most excited abut the new data is the depth which it provides. The 1940 census included questions that hadn't been asked before, in turn gathering a better sense of the nation's average income, home values, and employment statuses. A full list of the questions that were asked is available online via the Census Bureau.

The new data may also help researchers explore the impact of the New Deal, the economic recovery program often credited with lifting the nation out of the Great Depression.

However, David E. Kyvig, author of "Daily Life in the United States, 1920-1939" told NPR he expects the 1940 census to paint the program in a new light.

"We ought to be able to see more clearly how government spending bettered everyday life, confirmed Keynesian economic theory and revealed that, before the war, the New Deal did too little, rather than too much, to stimulate the U.S. economy," Kyvig told NPR in an interview.

For a better sense of what's included in the newly released records, visit the official 1940 census site. While the records are accessible to the public they won't be easily searchable until they've been entirely indexed.

The AP has provided instructions for delving into the data:

Here are step-by-step instructions on how to find records in the census:

1. To start, you'll need to know the address or approximate address of where the person or people were living by April 1, 1940.

Sources to find addresses include birth, marriage and death certificates; diaries; employment records; photographs; scrapbooks; Social Security application information; telephone books; or the 1930 census.

2. Using the address, you can then identify the enumeration district, a two-part number separated by a hyphen.

3. Once you have the enumeration district, you are ready to browse the census records.