The 2001 Current Population Survey (CPS) served as a tool for testing a sample expansion of the Annual Demographic Supplement and as a bridge to introduce new Census 2000-based population controls.
Sample Expansion
The Census Bureau tested a 28,000 household expansion in the interviewed sample for the CPS Annual Demographic Supplement in 2001. The original sample size of approximately 50,000 interviewed households for the 2001 CPS Annual Demographic Supplement was increased to approximately 78,000. The primary goal of the sample expansion was to produce more reliable estimates of low-income children without health insurance for the State Children’s Health Insurance Program (SCHIP) through reduced variances. Although the SCHIP sample expansion was specifically targeted toward producing better children’s health insurance estimates at the state level, other state estimates, as well as national estimates, improved. Further information about the SCHIP sample expansion is available on the internet at: www.bls.census.gov/cps/ads/adsmain.htm.
Change in Population Controls
The procedure used in developing estimates for the entire civilian noninstitutional population for the Current Population Survey (CPS) involves the weighting of sample results to independent estimates of the population by sex, age, race, and Hispanic/non-Hispanic categories. These independent estimates are developed by using civilian noninstitutional population counts from the decennial censuses and projecting them forward to current years using data on births, deaths, and net migration. Beginning with the 2001 CPS Annual Demographic Supplement, the independent estimates used as control totals for the CPS are based on civilian noninstitutional population benchmarks consistent with Census 2000. For further information about CPS weighting procedures, see Technical Paper 63RV, available at www.bls.census.gov/cps/tp/tp63.htm.
