http://www.census.gov/main/www/cen2000.html
Survey Unit: (household units)
Frequency: Every ten years
Time Periods: 1990 – 2000
Number of Observations: 16.6 million households and 43.5 million individuals most recently
Description:
The Decennial Census Long Form Sample is a 1-in-6 sample of all households in the U.S. The questions asked of this sample include age, race, sex, educational attainment, income, place of work, occupation, household relationships, housing unit characteristics, etc. Because these files are large, processing with them can be very time and resource intensive. In cases where there is no valid response for an individual (or household where applicable), the item is filled in using a system of allocation. Allocation consists of using the response of a similar observation to fill in a missing item. A great deal of documentation of the Decennial Census is available on the Census Bureau’s website.