U-1 Persons unemployed 15 weeks or longer as a percent of the civilian labor force. 
U-2 Job losers as a percent of the civilian labor force. 
U-3 Unemployed persons 25 years and over as a percent of the civilian labor force 25 years and over . 
U-4 Unemployed full-time jobseekers as a percent of the full-time labor force. 
U-5 Total unemployed as a percent of the civilian labor force (official measure) . 
U-6 Total full-time jobseekers plus half part-time jobseekers plus half total on 
part time for economic reasons, as a percent of the civilian labor force less 
half of the part-time labor force . 
U-7 Total full-time jobseekers plus half part-time jobseekers plus half total 
on part time for economic reasons plus discouraged workers, as a percent of the 
civilian labor force plus discouraged workers less half of the parttime labor 
force.   

MONTHLY LABOR REVIEW August 1982 bls.gov