Average skill levels in the economy increased over the 1989-97 period, primarily due to shifts in occupational employment within industries.
A little over half of the total change was caused by shifts within broad occupational groups, within specific industries. An example of this might be a shift toward clerical supervisors and away from secretaries and data processors in the clerical occupations within the services industry.
About one-third of the increase could be traced to shifts within industries but across broad occupational groups. One example would be the trend toward hiring more professional workers and fewer clerical workers in a wide variety of industries.
Skill levels increased only slightly due to shifts toward higher-wage industries. Such across-industry shifts were mostly in the service-producing sector and accounted for about one-tenth of the total increase in the economy’s skill level.
Bureau of Labor Statistics, U.S. Department of Labor, The Economics Daily, Shifts within and across occupations drive changes in skill levels at https://www.bls.gov/opub/ted/1999/sept/wk3/art05.htm (visited January 30, 2023).