The American Housing Survey (AHS) Protected Identification Key (PIK) Crosswalks are used to link ACS microdata files to other microdata files with a PIK variable. The American Housing Survey (AHS) is sponsored by the Department of Housing and Urban Development (HUD) and conducted by the U.S. Census Bureau. The survey has been the most comprehensive national housing survey in the United States since its inception in 1973, providing current information on the size, composition, and quality of the nations housing and measuring changes in our housing stock as it ages.
