Slide 25 of 29
Notes:
Public Use Microdata Areas (PUMAs) are geographic entities for which the U.S. Census Bureau provides specially selected extracts of raw data from a small sample of long-form census records. All personal identifying information has been removed from these records. The extract files are referred to as public use microdata samples (PUMS).
Public Use Microdata Areas must have a minimum census population of 100,000 and unlike 1990 cannot cross a state line. A 5-percent sample of the long-form records is extracted and presented in state files. Super-PUMAs, areas of 400,000 population, are combinations of PUMAs and represent the areas for which the Census Bureau provides a 1-percent file.
(Data users can use these files to create their own statistical tabulations and data summaries.)
Another new wrinkle for Census 2000 Public Use Microdata Areas is that the 5-percent PUMAs must nest within the 1-percent PUMAs whereas in 1990 the different sets could cover different areas.
