To produce this data collection, the principal investigators created a "uniform" series of Current Population Surveys: Annual Demographic Files (March) that have a rectangular file structure and use one set of documentation. These Current Population Survey (CPS) files are annual population surveys of the United States conducted by the United States Census Bureau and are often referred to as the March CPS Demographic Supplements. The files contain records for families selected in the samples as well as for each person in the families. Information is included on labor force activity, income, age, race, household structure, education, family relationships, occupation, and employment history.