Interest in the newly released US census of 1940 was so great that the government website was nearly paralysed shortly after the records became available.
Miriam Kleiman, spokesman for the US National Archives, said that the site registered more than 22 million hits in just four hours on Monday, from almost two million users.
The government released the records for the first time after 72 years of confidentiality expired.
It's the largest collection of digital information ever released by the National Archives. The records allow individuals and families to learn details about their past.
Susan Cooper, a second spokesman, said the problems began as soon as the information was released on the website. She termed the problems a "virtual traffic jam."
"We anticipate that this jam will ease up by this evening," Ms Cooper said. "The problem is, we just weren't expecting the huge volume that we got."
Computer experts were working on the site to bring it up to speed as soon as possible. Cooper did not give an exact time when the site would be fully operational.
"We're adding a lot more servers, a lot more muscle to the website," she said.
More than 21 million people still alive in the US and Puerto Rico were counted in the 1940 census. The census followed a decade when tens of millions of people in the U.S. experienced mass unemployment and social upheaval as the nation clawed its way out of the Great Depression and rumblings of global war were heard from abroad.
Monday's release includes digitized records for details on 132 million people. Access to the records is free and open to anyone online, but they are not yet searchable by name.
For now, researchers will need an address to determine a census enumeration district - a way to carve up the map for surveying - to identify where someone lived and then browse the records.
Every decade since 1942, the National Archives has made available records from past censuses. The records, which include names, addresses and income and employment information, are rich with long-veiled personal details.
Computer experts were working on the site to bring it up to speed as soon as possible. Cooper did not give an exact time when the site would be fully operational.
"We're adding a lot more servers, a lot more muscle to the website," she said.
More than 21 million people still alive in the US and Puerto Rico were counted in the 1940 census. The census followed a decade when tens of millions of people in the U.S. experienced mass unemployment and social upheaval as the nation clawed its way out of the Great Depression and rumblings of global war were heard from abroad.
Monday's release includes digitized records for details on 132 million people. Access to the records is free and open to anyone online, but they are not yet searchable by name.
For now, researchers will need an address to determine a census enumeration district - a way to carve up the map for surveying - to identify where someone lived and then browse the records.
Every decade since 1942, the National Archives has made available records from past censuses. The records, which include names, addresses and income and employment information, are rich with long-veiled personal details.