The number of persons working part-time for economic reasons increased 60 percent (by 2.112 million workers) between 1979 and 1985. Although total wage and salary employment is up since 1979, nearly one in five new positions is a part-time job filled by a worker unsuccessful in finding full-time employment. Sixty-two percent of those working part-time for economic reasons are in the wholesale and retail trades or service sector. Women constitute 62 percent of involuntary part-timers. Although 81 percent of involuntary part-time workers in 1985 were white, a Hispanic worker was nearly 1.5 times and a black worker was nearly twice as likely as a white jobholder to be underemployed. Two-thirds of those who worked part-time for economic reasons were adults; however, young adults were twice as likely to be underemployed. The number of involuntary part-time workers increased in all states between 1979 and 1984. Forty-one states had higher jobless rates in February 1986 than in 1979, before the recessions of 1980 and 1982. The real jobless rates in the communities with the 20 highest unemployment rates in February 1986 ranged from 22.7 to 40.9 percent. (This report includes eight tables summarizing data on involuntary part-time employment by industry/sector, sex, and state; metropolitan areas with the highest unemployment rates; and state-by-state unemployment rates.) (MN)