Two surveys, two units
Nonfarm payroll employment comes from the establishment survey. It counts jobs on participating employers’ payrolls. A person holding two covered payroll jobs can contribute two jobs to the total. The survey excludes categories such as most self-employment that can appear in household employment.
The household survey asks about people and their labor-force status. An employed person is counted once even if that person holds more than one job. Its population, survey design and definitions differ from those used for establishments. It is the source of the U-3 unemployment rate and participation measures.
The unemployment denominator
The U-3 unemployment rate divides unemployed people by the civilian labor force. The labor force includes employed and unemployed people, under the survey’s rules. It is not the entire U.S. population. Children, institutionalized people and other people outside the survey universe are not simply classified as unemployed.
People without a job who are not actively seeking work generally are outside the labor force, with specified treatment for temporary layoffs. The employment-population ratio uses the covered population as its denominator, while participation measures the labor force relative to that population. Each ratio describes a different relationship.
Why changes can diverge
Monthly sampling variation, coverage differences, population controls, seasonal adjustment and later revisions can all affect the published histories. A month when household employment and payroll employment move differently is not resolved by forcing one change to equal the other. Inspect the specific sources and the longer trend.
Job openings, hires and quits introduce another distinction: openings are a stock at the end of the month; hires and quits are flows during the month. Hires alone are not net job growth because separations also occur. Use each measure for the question it was designed to answer and keep its period and unit in the citation.