United States: 1980, 1990

All households and group quarters in identifiable cities.

CITYUS identifies the household's city within the United States if the household resided in one of the cities identified in a given sample.

This variable is essentially comparable across samples, but not all cities are identified in each year.

The 1980 sample allows the city of residence to be given for households living in many, but not all, cities with populations of 100,000+.

The 1990 sample divides the nation into Public Use Microdata Areas (PUMAs), containing between 100,000 and 199,999 residents. While PUMA boundaries are sometimes coterminous with city boundaries, they are not specifically designed to be so, and they often are not. This means that some of the residents of a given city were grouped in a PUMA with residents of other contiguous civil divisions. Therefore, we usually identified the city of residence only if the PUMA(s) comprising that city were completely coterminous with the city. In some cases, we identified the city of residence even though the PUMA boundaries did not strictly follow city boundaries. These were PUMA(s) that we judged to be relatively "uncontaminated" with residents from outside the city (usually less than 1% non-city).