Because there is no standard definition of S&E workers, this section uses multiple categorizations to measure the U.S. S&E workforce. In general, this section defines the S&E workforce to include people who either work in S&E occupations or hold S&E degrees. The application of S&E knowledge and skills is not limited to jobs with formal S&E titles; the number of college graduates reporting that their jobs require at least a bachelor’s degree level of knowledge in one or more S&E fields exceeds the number of workers employed in S&E occupations in the economy. Therefore, this section also presents data on the use of S&E technical expertise on the job to provide an estimate of the U.S. S&E workforce. The estimated number of scientists and engineers varies based on the criteria applied to define the S&E workforce.
U.S. federal occupation data classify workers by the activities or tasks they primarily perform in their jobs. The NSF and Census Bureau occupational data in this chapter come from federal statistical surveys in which individuals or household members provide information about job titles and work activities. This information is used to classify jobs into standard occupational categories based on the Standard Occupational Classification (SOC) system. In contrast, the BLS-administered OES survey relies on employers to classify their workers using SOC definitions. Differences between employer- and individual-provided information can affect the content of occupational data.
NSF has developed a widely used set of SOC categories that it calls S&E occupations. Very broadly, these occupations include life scientists, computer and mathematical scientists, physical scientists, social scientists, and engineers. NSF also includes postsecondary teachers of these fields in S&E occupations. A second category of occupations, S&E-related occupations, includes health-related occupations, S&E managers, S&E technicians and technologists, architects, actuaries, S&E precollege teachers, and postsecondary teachers in S&E-related fields. The S&E occupations are generally assumed to require at least a bachelor’s degree level of education in an S&E field. The vast majority of S&E-related occupations also require S&E knowledge or training, but an S&E bachelor’s degree may not be a required credential for employment in some of these occupations. Examples include health technicians and computer network managers. Other occupations, although classified as non-S&E occupations, may include individuals who use S&E technical expertise in their work. Examples include technical writers who edit scientific publications and salespeople who sell specialized research equipment to chemists and biologists. The NSF occupational classification of S&E, S&E-related, and non-S&E occupations appears in table
Other general terms, including science, technology, engineering, and mathematics (STEM), science and technology (S&T), and science, engineering, and technology (SET), are often used to designate the part of the labor force that works with S&E. These terms are broadly equivalent and have no standard definition.
The number of individuals who have S&E training or who reported applying S&E technical expertise in their jobs exceeds the number of individuals employed in S&E occupations. A relatively narrow definition of the S&E workforce consists of workers in occupations that NSF designates as S&E occupations. A much broader definition of an S&E worker, defined by SESTAT, includes any individual with at least a bachelor’s (or higher) degree in an S&E or S&E-related field of study or a college graduate in any field employed in an S&E or S&E-related occupation. The S&E workforce may also be defined by the technical expertise or training required to perform a job. Unlike information on occupational categories or educational credentials, information on the use of technical knowledge, skills, or expertise in a person’s job reflects that individual’s subjective opinion about the content and characteristics of the job. The next section provides estimates of the size of the S&E workforce using all three definitions.
Defined by occupation, the U.S. S&E workforce totals between 5.8 million and 6.0 million people according to the most recent estimates (table
As noted earlier, S&E degree holders greatly outnumber those currently employed in S&E occupations. In 2010, about 19.5 million college graduates in the United States had a bachelor’s or higher level degree in an S&E field of study (table
The majority of individuals with a highest degree in S&E reported that their job was either closely or somewhat related to their field of highest degree (table
The extensive use of S&E expertise in the workplace is also evident from the number of college graduates who indicate that their jobs require technical expertise at the bachelor’s degree level in S&E fields. According to the 2010 National Survey of College Graduates (NSCG), 16.5 million college graduates reported that their jobs require at least this level of technical expertise in one or more S&E fields (table
The S&E workforce has grown faster over time than the overall workforce. According to Census Bureau data, employment in S&E occupations grew from about 1.1 million in 1960 to about 5.8 million in 2011. This represents an average annual growth rate of 3.3%, compared to the 1.5% growth in total employment during this period. As a proportion of all employment, S&E occupational employment grew from 1.6% in 1960 to 4.1% in 2011.
Data from more recent years indicate that trends in S&E employment compared favorably to overall employment trends during and after the 2007–09 economic downturn. OES employment estimates from BLS indicate that the size of the S&E workforce rose slightly from 5.4 million in May 2006 to 5.8 million in May 2009 and then remained relatively steady through May 2012, reaching a level of 6 million. In contrast, the total workforce during this period declined from 133 million in May 2006 to 131 million in May 2009 and then to 130 million in May 2012. The broader STEM aggregate (including S&E technicians, S&E managers, etc.) remained relatively steady at 7.9 million in May 2012, compared with 7.8 million in May 2009 and 7.4 million in May 2006. BLS projects that between 2010 and 2020 S&E occupations—particularly computer and mathematical sciences, life sciences, and social sciences-related occupations—will grow at a faster rate than the total workforce. (See sidebar, “Projected Growth of Employment in S&E Occupations.”)
The growth in the number of individuals with S&E degrees in recent years can be examined using data from NSF’s SESTAT. The number of S&E highest degree holders employed in the United States grew from 9.6 million to 11.4 million between 2003 and 2010, with most broad fields exhibiting growth (figure
A number of factors likely contributed to the growth in the U.S. S&E labor force over time: the rising demand for S&E skills in a global and highly technological economic landscape; increases in U.S. S&E degrees earned by women, by racial and ethnic minority groups, and by foreign-born individuals; temporary and permanent migration to the United States of those with foreign S&E educations; and the relatively small proportion of scientists and engineers retiring from the S&E labor force. The demographic sections of this chapter provide data on aging and retirement patterns of scientists and engineers as well as on S&E participation by women, by racial and ethnic minorities, and by foreign-born individuals.
Workers in S&E occupations have undergone more formal education than the general workforce (figure
Compared with the rest of the workforce, a very small minority of those employed in S&E occupations have only a high school degree. Many individuals enter the S&E workforce with marketable technical skills from technical or vocational schools (with or without an earned associate’s degree) or college courses, and many acquire these skills through workforce experience or on-the-job training. In information technology, and to some extent in other occupations, employers frequently use certification exams, not formal degrees, to judge skills. (See sidebar, “The U.S. S&E Workforce Without a Bachelor’s Degree” and the discussion in chapter 2.)
According to the 2010 SESTAT data, the vast majority (81%) of college graduates employed in S&E occupations have at least one S&E degree (table
NSF’s SESTAT provides information on the degree and occupational choices of scientists and engineers in the United States, thus enabling a comparison of the interplay between degree and occupation for members of the S&E workforce with and without a highest degree in an S&E discipline. Although an S&E degree is often necessary to obtain S&E employment, the data indicate that many individuals with S&E degrees pursue careers outside of S&E. The majority of workers with S&E training who work in non-S&E jobs reported that their work is nonetheless related to their S&E training, suggesting that the application of S&E skills and expertise extends well beyond the jobs NSF classifies as S&E. (The next section, “S&E Workers in the Economy,” provides data on R&D activity of scientists and engineers employed in S&E and non-S&E occupations.)
Only about half of S&E highest degree holders are employed in an S&E (35%) or S&E-related (14%) occupation; the rest are employed in non-S&E occupations. Figure 3-5 shows the occupational distribution of the S&E workforce with S&E, S&E-related, and non-S&E highest degrees. The largest category of non-S&E jobs for S&E highest degree holders is management and management-related occupations (2.1 million workers), followed by sales and marketing occupations (995,000 workers) (appendix table
Most individuals who have S&E highest degrees but are not working in S&E occupations do not see their field of highest degree as entirely irrelevant to their work. Rather, most indicate that their jobs are either closely (35%) or somewhat (32%) related to their highest degree field (table
Unlike members of the S&E workforce with an S&E highest degree, half or more of the S&E workforce with S&E-related or non-S&E highest degrees obtain employment in their respective broad occupational category (figure
The pattern of significant proportions of S&E highest degree holders obtaining employment in areas other than S&E occupations has been robust over time. SESTAT data from 1993 indicate that 36% of all scientists and engineers with S&E highest degrees were employed in S&E occupations, and the rest held positions in areas other than S&E.
The proportion of S&E highest degree holders who go on to work in S&E occupations varies substantially by S&E degree fields and levels. Individuals with social sciences highest degrees are the least likely to work in S&E occupations; these individuals primarily obtain non-S&E employment (figure
This pattern of field differences generally characterizes individuals whose highest degree is at either a bachelor’s or master’s degree level. At the doctoral level, the size of these field differences shrinks substantially (figure
The pattern of a stronger relationship between S&E jobs and S&E degrees at higher degree levels is robust across career stages, as seen in comparisons among groups of bachelor’s, master’s, and doctoral degree holders at comparable numbers of years since receiving their degrees (figure