These skill categories reflect only average skill demands within broad occupational categories. Some occupations within the technical and managerial categories actually require less than a bachelor’s degree, while some in the middle categories might require only high school, and some in the service category may require more than high school. Therefore, whenever possible, we supplement our analysis of broad categories with those of detailed occupations. Some prominent examples of these occupations appear in Table 1. As the data indicate, many of these occupations employ hundreds of thousands of workers and their annual earnings reach as high as $70,000.
Low-Skill Middle-Skill High-Skill
Source: Tabulations by authors from the Bureau of Labor Statistics web site. Note: High-skill occupational categories are Management and Financial Operations and Professionals and Related Occupations; middle-skill categories are Sales and Related Occupations, Office Administrative Support, Construction, Installation and Repair, Production Occupations, and Transportation and Material Moving; and low-skill categories are Service Occupations and Farming, Fishing, and Forestry.
Data on the last two decades confirm that jobs have expanded faster in both high-skill and low- skill positions than in middle-skill positions. But these trends do not herald a polarized or barbell economy. Middle-skill jobs still make up roughly half of all employment today, even though they decreased their share of total employment from about 55 percent to 48 percent between 1986 and 2006 (Figure 1). What’s more, this conclusion is not very sensitive to exactly which occupational categories we include in each broad skill group
While the share of jobs in the middle category declined, professional and related occupations rose from 17 percent in 1986 to more than 20 percent in 2006 and managerial positions increased from about 12 to 15 percent of total employment. Low-skill (service) jobs barely increased their share from 15 to 16 percent of total employment. Jobs in sales and office occupations fell from about 28 to 25 percent of all jobs. Production positions dropped as well, from 9 to 6.5 percent. Despite these declines, sales, office, and production occupations still accounted for about one-third of all jobs in 2006.
Positive trends in some occupations illustrate the persistence of employment in middle-skilled fields. Since 1986:
Medical therapists—including middle-skill categories such as respiratory, recreational,
and radiation—and their aides have expanded sharply, rising about 30 percent.