Archive of Census Related Products (ACRP): 1990 ZIP Equivalency Files

The 1990 Zip Equivalency Files portion of the Archive of Census Related Products (ACRP) contains population and housing data derived from the U.S. Census Bureau's 1990 STF3B header file. The data are available at the census block and census blockgroup levels, and encompass 5-digit zip codes, POLygon IDentification (POLID) block fields that correspond to the POLID of the Tiger-based boundary file, and population centroids. This portion of the ACRP is produced by the Center for International Earth Science Information Network (CIESIN).