OSCILAT: Optimized Spatial Census Information Linked Across Time

OSCILAT (Optimized Spatial Census Information Linked Across Time) is a data set that provides high-quality georefence information for 1990, 2000, and 2010 U.S. decennial census microdata for both persons and housing units, including Puerto Rico in 2000 and 2010. The data set includes two types of georeference information: (1) optimized geographic coordinates (latitude and longitude) and (2) census block identifiers. Each of these types of information is “linked across time†in a different way. First, the optimized geographic coordinates are derived, wherever possible, from the most recent corresponding source of census spatial information, e.g., by “linking†a 1990 microdata record to coordinates for the corresponding address in the 2020 Master Address File Extract (MAFX). Second, OSCILAT “links†every microdata record to multiple census years’ geographic units by identifying not only a contemporary block ID (e.g., the 2000 block where a 2000 census respondent resided) but also 2010 and 2020 block IDs (e.g., the 2010 and 2020 blocks where a 2000 census respondent resided). These block IDs can be used to associate 1990, 2000 or 2010 census responses with any higher level of 2010 or 2020 census geography (census tracts, counties, etc.), thereby facilitating longitudinal comparison with consistent spatial units.