American Housing Survey Series

The American Housing Surveys (AHS), prior to 1984 called the Annual Housing Surveys, were first conducted in 1973 by the United States Bureau of the Census. This series comprises two types of data collections: a national survey of housing units, and surveys of housing units in selected metropolitan areas. The interviews cover core questions that are repeated each year, and an additional set of questions on recurring or one-time supplemental topics. The national data were collected annually through 1981 and have been collected every two years since that time. The metropolitan-area data are collected on a continuous basis and are reported annually. Through 1996, the national data were released by the Census Bureau in two forms: the National Core File and the National Core and Supplement (called the "National" Files by ICPSR). Beginning with the 1997 data, these were combined by the Census Bureau into one collection, called the National Microdata. The metropolitan-area data were originally released as SMSA Files, MSA Files, MSA Core Files, MSA Core Question Files, and MSA Core and Supplement Files. In 1997, the metropolitan-area data were combined by the Census Bureau into one collection, called the Metropolitan Microdata. Supplemental data on transportation were released in Travel-to-Work Files for some survey years, in addition to the data on this topic contained in the national datasets. Other recurring supplementary topics include mobility, second and mobile homes, disabilities, cars and major appliances, energy conservation, housing modifications, and additional questions on housing and neighborhood quality. An important feature of these surveys is that generally the same housing units remain in the sample year after year, and it is the housing unit rather than its occupants that is followed. For all American Housing Surveys, data collected on income can be used in conjunction with annual housing expenditures to estimate the average percentage of families' and primary individuals' incomes spent on housing. Households that have moved in the 12 months prior to enumeration are asked to provide comparative information on the current and previous residences of household heads. In 1997, the AHS was redesigned to present the data in multiple separate subject-matter files, and computer-assisted personal interviewing software was used to conduct all interviews, which allowed new responses to some questions. Therefore, users are asked to use caution when comparing prior years' data with data collected after 1996.