Although the United States is more than 200 years old, its housing inventory is young. In 2001, just 8.3 percent of all American housing was built before 1920. This report examines housing units built 82 years or more ago (which are referred to as old units), and compares their characteristics with those of units built after 1989 (which are referred to as new units). The data are from the 2001 American Housing Survey (AHS) National Sample.