ICAR Research Data Repository for Knowledge Management

The master crosswalk file maps U.S. ZIP codes to their respective ZIP Code Tabulation Areas (ZCTAs), capturing the discrepancies and characteristics of the ZIP-ZCTA relationships across the different yearly UDS crosswalks.

ZCTAs allow for consistent analysis over time while accommodating changes in the underlying ZIP Code system and geographic boundaries. It helps ensure that researchers and policymakers are working with data that accurately reflects the geographic realities of their study period.