by Joan Burrelli
The relatively low proportion of women in academic science and engineering (S&E) has been the topic of numerous recent books, reports, and workshops. (See for example, Powell 2007, DOE/NSF/NIH 2006, National Academies 2007.) Data for 2006 show that women continue to constitute a much lower percentage of S&E full professors than their share of S&E doctorates awarded in that year. Even in psychology, a field heavily dominated by women, women were less than half of all full professors, even though they earned well more than half of doctorates in 2006.
This InfoBrief examines the trends from 1973 to 2006 in the employment of women faculty and in the percentages of full professors and of tenured faculty who are women. The trends are examined by field of doctorate, Carnegie classification of employer, marital status, and the presence of children in the home. Because the S&E doctorate holders employed in academic institutions in 2006 were awarded their doctorates over a span of about three decades, these trends are examined against the background of changing percentages of S&E doctorates earned by women over time, starting with the 1958 degree year.
Trends in S&E Doctoral Degrees
The proportion of S&E doctoral degrees earned by women has risen considerably in the past several decades, reaching 40% in 2006 compared with 8% in 1958 (table 1). During this period, women made gains in all major S&E fields, but considerable differences by field remain. Women earned half or more of doctorates in psychology (71%) and the life sciences (52%) in 2006 but considerably less than half of doctorates in mathematics (30%), physical sciences (29%), computer sciences (21%), and engineering (20%). Although low for the latter fields, these shares are considerably higher than the corresponding values in 1958 (6%, 4%, and less than 1%, respectively, for mathematics, physical sciences, and engineering).
Table 1 Source Data: Excel file
Employment in Colleges and Universities
The number of women with S&E doctorates employed in colleges and universities rose continuously between 1973 and 2006, while that of men rose more slowly, especially in the 1990s. Reflecting these trends, women constituted 33% of all academic S&E doctoral employment and 30% of full-time faculty in 2006, up from 9% and 7%, respectively, in 1973 (NSB 2008).
Academic jobs constituted declining shares of employment for both men and women with S&E doctorates through the 1970s and 1980s, thereafter fluctuating in narrow ranges. From 1993 to 2006, about half of female and 41%–45% of male doctoral scientists and engineers were employed in the academic sector, compared with 67% and 54%, respectively, in 1973. The shift away from academia over the period was accompanied by rising shares of doctorate holders employed in the business sector—for women from 7% to 19% and for men from 25% to 33% by 2006 (table 2).
Table 2 Source Data: Excel file
Employment sector differences between men and women primarily reflect differences in field of doctorate, as women continue to be less likely than men to earn doctorates in engineering or physical sciences (tables 3 and 4), fields in which relatively high percentages of individuals are employed in the business sector. Within specific fields, academic and industry employment shares of men and women are more similar, but consistently higher percentages of women than men are in academic jobs. Exceptions are physical and social sciences, with only minor and statistically not significant sex differences in academic employment.
Table 3 Source Data: Excel file
Table 4 Source Data: Excel file
Tenure and Rank
Women's share of full-time tenured or tenure-track S&E faculty increased over the period for which data on tenure status are available, from 10% in 1979 to 28% in 2006. Trends for most major S&E fields were in the same direction (table 5). For example, women were about 1% of full-time tenured or tenure-track faculty in engineering in 1979 and 11% in 2006.
Table 5 Source Data: Excel file
These gains in tenured and tenure-track positions, as well as corresponding gains in full professor positions, reflect a rising inflow of female doctorate recipients in recent years, combined with nearly level numbers of men. As a result, women hold a larger share of instructor and assistant professor positions (42%) than of associate (34%) or full professor (19%) positions (NSB 2008). Women's shares of all these full-time positions rose substantially between 1973 and 2006.
Women's share of full-time full professors rose from 5% in 1973 to 19% in 2006 (table 5). Women were also an increasing percentage of full-time full professors in most major S&E fields.
Among S&E doctorate holders employed full time in academia, a much higher percentage of women than men earned their doctorates relatively recently. In 2006 about two-thirds of women and 45% of men so employed had received their doctorates after 1984, and 26% of women vs. 15% of men had earned them since 1994 (table 4).
Consequently, women are a larger share of full-time tenured or tenure-track faculty among those with recent S&E doctorates than they are among all S&E faculty. In 2006 women were 42% of full-time tenured or tenure-track faculty with recent (within 7 years) S&E doctorates and 28% of all full-time tenured or tenure-track faculty. Likewise in 2006, women were 28% of full-time full professors with relatively recent S&E doctorates (i.e., those earned from 1991 to 1995) but were 19% of all full-time full professors with S&E doctorates (figure 1).
Figure 1 Source Data: Excel file
Women's lower percentage of S&E doctorate recipients in previous years accounts for some of the difference between women's current percentage of full-time tenured or tenure-track faculty or of full-time full professors and women's current percentage of S&E doctorate recipients. The fraction of S&E doctorates earned by women from 1958 to 2004 (28%) is the same as women's fraction of full-time tenured and tenure-track S&E faculty in 2006 but remains higher than women's percentage of S&E full-time full professors in 2006 (figure 1).
Employment in Research Institutions
Among S&E doctorate holders, women were an increasing share of tenured or tenure-track faculty and of full professors in all types of academic institutions, but they remained a lower percentage of tenured or tenure-track faculty and of full professors with S&E doctorates at Carnegie research institutions in 2003 than they were at medical schools or master's-granting institutions (table 6). Women were 16% of full-time full professors with S&E doctorates at research institutions in 2003, up from 2% in 1973, and women were 23% of full-time tenured or tenure-track faculty with S&E doctorates at research institutions in 2003, up from 8% in 1979.
Table 6 Source Data: Excel file
Marital Status and Presence of Children in the Home
Family characteristics, specifically marital status and the presence of children in the home, were found to be related to women's chances for earning tenure and for holding either an associate or full professor rank in a 2004 National Science Foundation (NSF) longitudinal analysis of the academic career paths of men and women (NSF/SRS 2004). Female doctoral S&E faculty are less likely than their male colleagues (67% vs. 84%) to be married. They are also less likely to have children living with them (42% vs. 50%) (table 4).
Trends in women as a percentage of tenured or tenure-track faculty and full-time full professors by marital status and the presence of children in the home mirror the trends discussed earlier among all S&E faculty (tables 7 and 8). Women with S&E doctorates represent an increasing share of tenured or tenure-track faculty and full-time full professors, irrespective of marital
status or the presence of children in the home. However, women were higher percentages of unmarried tenured or tenure-track faculty and full-time full professors than they were of those who were married, and they were a higher percentage of those without children than of those who had children in the home. Furthermore, numerical increases in the percentages of full-time full professors over time for unmarried women and women without children were greater than those for married women and women with children.
Table 7 Source Data: Excel file
Table 8 Source Data: Excel file
Women represent increasing shares of tenured and tenure-track faculty and of full-time full professors with S&E doctorates. To a large degree, these gains reflect women's increase in the percentage of S&E doctorates awarded. By 2006 women's share of tenured and tenure-track faculty was the same as their share of 1958–2004 S&E doctorates; however, their share of S&E full professors remained lower than their share of 1958–2004 S&E doctorates. Unmarried women and women without children made greater numerical gains in their percentage of full professors from 1973 to 2006 than married women or women with children.
The main source of the data for this InfoBrief is the NSF Survey of Doctorate Recipients (SDR), a survey conducted biennially from 1973 to 2003 and in 2006. The SDR provides data on people who have earned science, engineering, and health doctorates from U.S. institutions and who are employed in the United States. Thus, the faculty data included in this report refer only to U.S. faculty with science, engineering, and health doctoral degrees from U.S. institutions. The Carnegie classification used in this InfoBrief is the 1994 version of the Carnegie Foundation for the Advancement of Teaching's classification of academic institutions. Because the 2006 SDR used the 2005 classification system, data were presented only from 1973 through 2003. All the academic employment estimates in this InfoBrief are based on sample data and are subject to sampling errors. Generalized variance functions were used to estimate the standard errors of the estimates, and statements made about the differences are statistically significant at the .05 level or less. Further SDR-related information can be found at http://www.nsf.gov/statistics/doctoratework/. For further information on this InfoBrief, contact Joan Burrelli.
 Joan Burrelli, Division of Science Resources Statistics, Science and Engineering Indicators Program, National Science Foundation, Suite 965, 4201 Wilson Boulevard, Arlington, VA 22230 (firstname.lastname@example.org; (703) 292-7793).
 In this InfoBrief, life sciences doctorates include those in health and biomedical sciences.
 In this InfoBrief, trends in doctorate conferral begin in 1958, about the upper limit for year of doctorate of S&E doctorate holders in the U.S. labor force in 2006. Starting in 1958 also allows a period of 15 years after doctorate receipt for S&E doctorate holders surveyed in 1973, which is sufficient time for many to be appointed to full professorships.
 Data on computer science doctorates were not collected until 1978.
 Full-time faculty include full, associate, and assistant professors and instructors employed 35 hours or more per week in 2- or 4-year colleges or universities.
 In computer sciences the number of women in earlier years was too small for reliable estimates, and the decline from 1999 to 2006 in the percentage of full professors who were women is not statistically significant.
 Differences between research institutions and other doctoral and baccalaureate institutions were not statistically significant.
Powell K. 2007. Beyond the glass ceiling. Nature 448:98–100.
National Academies. 2007. Beyond Bias and Barriers: Fulfilling the Potential of Women in Academic Science and Engineering. A Report of the Committee on Maximizing the Potential of Women in Academic Science and Engineering of the Committee on Science, Engineering, and Public Policy. Washington, DC: National Academies Press.
National Science Board. 2008. Science and Engineering Indicators 2008. Arlington, VA: National Science Foundation.
National Science Foundation, Division of Science Resources Statistics (NSF/SRS). 2004. Gender Differences in the Careers of Academic Scientists and Engineers. Special Report NSF 04-323. Alan I. Rapoport, project officer. Arlington, VA. Available at http://www.nsf.gov/statistics/nsf04323/.
U.S. Department of Energy, National Science Foundation, National Institutes of Health (DOE, NSF, NIH). 2006. Report on the Workshop on Building Strong Academic Chemistry Departments Through Gender Equity. Arlington, VA: National Science Foundation. Available at http://www.chem.harvard.edu/groups/friend/GenderEquityWorkshop/.