Over the past 25 years, minor adjustments to Poland’s administrative (territorial) division happened almost every year. This typically involves granting town rights. There have also been cases of changing county (KTS-5)\/municipality (KTS-6) names and including or separating a municipality from another administrative unit. Most of these changes modified the unique identification code of the municipality in the TERYT administrative registry. Such adjustments can complicate historical time series analysis, especially from databases originating outside the Statistics Poland datasets. The\u00a0crosswalks include all TERYT codes for municipalities and counties applicable in a given year and a reason for changes for each unit.<\/p>\n\n\n\n