The 1940 census was released by the National Archives in April, offering those interested the opportunity find out where their relatives grew up.
But experts have been privy for many years to information about housing in 1940, when ramped-up war production finally brought an end to the Great Depression.
What was it like? Well, 18 percent of housing was in need of major repair. That meant that almost 7 million of the 37.4 million dwellings in the United States were dilapidated.
Nearly 11.5 million dwellings had no running water, 13 million had no private flush toilets, 16 million had no bathtub or shower.
One-fifth of housing was considered overcrowded, with almost 10 percent severely overcrowded -- one result of the Depression. Though the population had increased by about 10 million since the 1930 census, only five million housing units had been built, adding to the dire situation.
Economists say that the United States is now emerging from the worst economic downturn since the Great Depression. And, with residential construction well below the 1.5 million units considered a "normal" year's output, some observers have been predicting a pending shortage.
Predicting how much housing is needed involves a complex calculus that weighs hard statistics (new-home starts, sales of previously owned homes) against a certain amount of demographic tea-leaf reading (household-formation forecasts). Thus, there isn't complete consensus on what will be enough.
Data from the National Association of Realtors show that the United States needs to build 1.3 million to 1.7 million housing units annually to keep pace with yearly household formations averaging 1 million to 1.4 million, in addition to replacing the 300,000 obsolete dwellings that are razed each year.
What about existing homes?
The Department of Housing and Urban Development's method for measuring quality of homes classifies only 1.5 percent as severely inadequate. Under the HUD classification, 5.3 million conventional housing units are either moderately or severely inadequate, and in only 1.7 million of these cases is the inadequacy of the units severe.
The National Association of Home Builders, the new-home industry trade group, proposes that the percentage is much higher, which "helps explain why prices are sometimes lower than expected," said association economist Paul Emrath.
His estimate is that 10 million existing houses fall into the "physically inadequate" category, almost double the number usually reported as inadequate.
The builders group proposes these criteria as making a single-family house inadequate: missing siding, broken windows, holes, cracks or crumbling foundations, holes in the floor or sagging roofs.
Harris Gross, a Cherry Hill-based home inspector, said relatively few of the houses he is hired to inspect have these problems. He said perhaps 15 percent are missing siding, 10 percent have broken windows, 15 percent have cracks or crumbling foundations, and 1 percent have holes in the floor or sagging roofs.
These items "don't begin to fully capture what would, in my mind, define inadequate housing," said Gross, who cited water leaks from pipes and roofs and malfunctioning furnaces as examples.
Here is what HUD considers moderately inadequate housing:
*Repeated toilet breakdowns lasting six hours or more.
*Main heating equipment consisting of unvented room heaters.
*Lack of complete kitchen facilities.
It is doubtful that a buyer who requires a mortgage to buy a house would be able to obtain financing if the house is not habitable, said Noelle Barbone, office manager at Weichert Realtors in Media.
"Substandard housing would require a specific buyer," she said. "So, a buyer who is interested in buying such a property would need to pay for it in cash."
Every property can be sold; it is a matter of finding the right buyer for it, she said. It takes someone who has enough money to bring it up to par or someone with a solid construction background who would not be turned off by the house's condition.
While the Centers for Disease Control and Prevention follows the HUD/American Housing Survey definition, the agency's interest is focused on who is forced to live there.
A 2011 study based on 2009 AHS research found that women were more likely to occupy inadequate housing units than men.
In 2009, non-Hispanic blacks had the highest odds of people living in inadequate housing, followed by Hispanics, American Indians/Alaskan natives and Asians/Pacific Islanders, when compared with non-Hispanic whites.
In 2009, people earning an annual salary of $24,999 were almost five times more likely to live in inadequate housing than those earning $75,000.
The CDC report said that of the 110 million housing units in the United States, 5.8 million are classified as inadequate and 23.4 million are considered unhealthy.
"Inadequate and unhealthy housing disproportionately affects the populations that have the fewest resources," the report stated.