U.S. Department of Commerce

Current Population Survey (CPS)

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Sampling

The CPS sample is a probability sample designed primarily to produce national and state estimates of labor force characteristics of the civilian non-institutional population 16 years of age and older. The sample consists of independent samples in each state and the District of Columbia, and each state sample is specifically tailored to the demographic and labor market conditions that prevail in that particular state.

About 60,000 housing units are required in order to meet the national and State reliability criteria, drawn from 824 sample areas. Sample sizes are determined by reliability requirements that are expressed in terms of the coefficient of variation or CV. The coefficient of variation is a relative measure of the sampling error and is calculated as sampling error divided by the expected value of the given characteristic. Sufficient sample is allocated to maintain, at most, a 1.9-percent coefficient of variation on national monthly estimates of unemployment level, assuming a 6-percent unemployment rate. This translates into a change of 0.2 percentage point in the unemployment rate being significant at a 90-percent confidence level. For each of the 50 States and for the District of Columbia, the design maintains a coefficient of variation of at most 8 percent on the annual average estimate of unemployment level, assuming a 6-percent unemployment rate.

Additional detail on the sample design and preparation is available from Chapters 3 and 4 of the “Current Population Survey, design and methodology” (Technical paper 66, October 2006).


Source: U.S. Census Bureau | Current Population Survey (CPS) |  Last Revised: 2013-04-22T15:03:50.386-04:00