Archives counts on microfilm

In 2072, the public will be allowed to view digital versions of census questionnairesthat more than 100 million Americans filled out last year. Until then, theNational Archives is turning to nondigital technology to preserve the records.

The Census Bureau converted the questionnaires, which originally wereon paper, to digital format last year. However, the high cost of keepingdigital records readable for the next seven decades is prompting the Archivesto convert them to microfilm for long-term storage.

"If we preserved them digitally, we would have to migrate them every10 years or so" as new digital formats are developed and old ones discarded,said Susan Cooper, spokeswoman for the National Archives and Records Administration.

The cost of repeatedly migrating — reproducing each image in progressivelynew formats — could be enormous, she said. But the danger of not migratingthe Census questionnaires is that the software and hardware needed to readthem in today's formats likely will no longer exist in 70 years. The questionnairesmust be kept sealed for 72 years to nullify privacy concerns.

The solution, the Archives decided, is microfilm. Unlike digital formats,"microfilm is microfilm — the technology does not change," Cooper said."We feel very confident that we will be able to read this stuff in 72 yearswhen we are ready to convert it" back into digital documents.

In November, the Census Bureau hired Lockheed Martin Corp. to beginplanning for converting 625 million pages of census forms on digital tapeinto microfilm images. According to the Census Bureau, the original paperforms have been shredded and recycled.

In all, the Census Bureau distributed 98.7 million short census formsand 20.3 million long forms to collect trove of data on 281.4 million peopleliving in the United States.