U1-U6 is ...
- U-1 Persons unemployed 15 weeks or longer, as a percent of the civilian labor force
U-2 Job losers and persons who completed temporary jobs, as a percent of the civilian labor force
U-3 Total unemployed, as a percent of the civilian labor force (official unemployment rate)
U-4 Total unemployed plus discouraged workers, as a percent of the civilian labor force plus discouraged workers
U-5 Total unemployed, plus discouraged workers, plus all other persons marginally attached to the labor force, as a percent of the civilian labor force plus all persons marginally attached to the labor force
U-6 Total unemployed, plus all persons marginally attached to the labor force, plus total employed part time for economic reasons, as a percent of the civilian labor force plus all persons marginally attached to the labor force
NOTE: Persons marginally attached to the labor force are those 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 past 12 months. Discouraged workers, a subset of the marginally attached, have given a job-market related reason for not currently looking for work. 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. Updated population controls are introduced annually with the release of January data.
Source: Bureau of Labor Statistics
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