How accurate are the unemployment figures?

Household Survey (also Current Population Survey) -- The household survey generates the unemployment rate from a statistically designed monthly sampling of roughly 60,000 households. Other surveys, such as the annual poverty survey, often are piggybacked on the employment questions. The survey measures the number of people who have jobs.

Payroll Survey (also Establishment or Current Employment Statistics Survey) -- The payroll survey generates an estimate of the number of nonfarm jobs in the U.S. economy, based on a monthly non-random sampling of payroll tax filings of about 160,000 U.S. corporations and government agencies. The survey measures the number of jobs (some individuals hold more than one job).

The household survey is conducted during the week that includes the 12th of the month. The payroll survey is conducted as of the payroll period that includes the 12th of the month. Other than for seasonal factors, the household survey gets revised only with series or population redefinition. The payroll series is revised for two months following the initial release and then again in an annual benchmark revision.

Where the household survey includes farm workers, the self-employed and workers in private homes, the payroll survey does not. The payroll survey counts jobs, making no adjustment for multiple jobholders. Yet, adjusting for all differences, the BLS never has been able to reconcile the two series within one million jobs.

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The Bureau of Labor Statistics (BLS) maintains six unemployment figures, U-1 through U-6, but the media only report U-3. The most inclusive figure, U-6, the BLS defines as "Total unemployed, plus all marginally attached workers, plus total employed part time for economic reasons, as a percent of the civilian labor force plus all marginally attached workers" where the following definitions apply:

Marginally attached workers are persons who currently are neither working nor looking for work but indicate that they want and are available for a job and have looked for work sometime in the recent past.

Discouraged workers, a subset of the marginally attached, have given a job-market related reason for not currently looking for a job.

Persons employed part time for economic reasons are those who want and are available for full-time work but have had to settle for a part-time schedule.

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