ZIP to County Crosswalk

The following crosswalks are the result of a data pipeline that pulls crosswalks from the U.S. Department of Housing and Urban Development (HUD) database, compiling a comprehensive ZIP --> FIPS crosswalk from 2010 to 2023. The crosswalks are available in four different forms: "one2one": one row, per ZIP code, per year. Each ZIP is matched to its best matching FIPS code. "one2few": Potentially multiple rows, per ZIP code, per year. All FIPS codes with a non-zero number of addresses for a given ZIP code are returned. "one2one_summy" and "one2few_summy" return the same respective types of data as the above, but summarize across chunks of years. Further description of these datasets, as well as code to reproduce and adjust results according to certain parameters, is available at the Github repo.