Transcript The U.S. Decennial Census of Population and Housing from

The U.S. Decennial Census of
Population and Housing from an
Archival Perspective
Thomas E. Brown
U.S. National Archives and Records
Administration
Archival values
• Evidential value
– “evidence of the organization, functions,
policies, decisions, procedures, operations, or
other activities of the Government”
• Informational value
– “because of the informational value of the data
contained therein”
1942: Schedules for 1790-1870
• Background:
– 1790-1870 publicly available
– Census Bureau moving to a new building
– Microfilming completed
• Appraisal: established value to historians,
sociologists, economists, genealogists, and
general public.
1952: Appraisal of Microfilm
• Background:
– NARS microfilming 1950 Census schedules
– Volume of paper schedules growing
– Statutory restrictions expires after 50 years
• Appraisal:
– Microfilm in place of paper
– Loss of information on microfilm
• Issue: Transfer date because restrictions
Restriction Question
• Statutory restrictions expire after 50 years
unless the Archivist extends
• Archivist offer to extend Census restriction
before Congress
• Why 72 years?
– Longest extension that would open the 1880
Census immediately
Congressional Approval of
72-Year Rule
• FOSDIC eliminated post-Census
microfilming
• 1890 Census in 1962: non-issue
• 1900 Census in 1972
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Census objected
Attorney General backed NARS
Congress backed NARS
1980 Census forms
Statistical Confidentiality Act of 2002
1979: Appraisal of Data Files
• Census microdata files
– Appraisal: “overall informational value is
formidable”
• Public Use Microdata Samples (PUMS) &
Summary Tape Files (STFs)
– Appraisal: “conveniently prepared according to
geographic characteristics which . . . enhances
the informational value”
2000: Appraisal of ICRF and
Images
• Replacement of FOSDIC
• Digital images
• Individual Census Record File
– Standard data file in ASCII
– First time names in digital Census files
– Basic records of the Census
• Destroy paper and scanned images
Opposition to Disposal of Images
• Congressman Waxman
– Historical series 1790-1990
– Marginalia
– Inaccurate scanning
• Images removed from records schedule
• ICRF: “very significant secondary value for
future genealogical, historical, statistical,
economic and demographic research”
Resubmission of Images for
Appraisal
• On the Census 2000 Comprehensive
Records Schedule
• Public Comments
– Two Congressmen
– Five social scientists
– Six genealogists
• Echoed Congressman Waxman
NARA Appraisal of Images
• ICRF: Basic records from Census 2000
• Practical considerations
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700 million page images
increase Archives holdings by 17.5%
430 million pages images blank
estimated 60 terabytes ($5.3-$10.5 million
annually)
– revised estimate: 160 terabytes
Resolution
• Withdrew images from the comprehensive
records schedule
• Reauthorization of NHPRC
• Third records schedule: images permanent
Denouement
• NARA lacked capability to preserve images
• Solution: Computer Output Microfilm
(COM)
• New schedule: images temporary, COM
permanent
• In 2072, NARA will digitized microfilm if
desired
Conclusion
• Most cost effective contemporary formats
– 1942: Paper
– 1952: Microfilm
– 1979: Magnetic computer tapes
• Inconsistent standards
– 1952: Accepted data loss
– 2000: Any data loss unacceptable