Donna Bobbitt-Zeher

The differences between men’s and women’s wages narrowed considerably during the second half of the twentieth century. While women averaged about 60 percent of men’s earnings in the 1960s and 1970s, by the end of the century, women averaged about three-fourths of men’s earnings. Closer inspection suggests that the gap narrowed fastest during the 1980s, with slower declines and stagnation in the 1990s and early 2000s (see, for example, Institute for Women’s Policy Research 2010). Yet a meaningful gap remains. In 2008, working women still earned only about 77 percent of what their male counterparts earned (Institute for Women’s Policy Research 2010). For young workers just beginning their careers, the gap is smaller but still significant: these women generally earn around 15 to 20 percent less than their male counterparts (Marini and Fan 1997; U.S. Department of Labor, Bureau of Labor Statistics 2004).

Research indicates that trends in the gender income gap vary across educational levels. For example, Blau found declines in the income gap across all levels of education. However, she also found that the gender income gap had shrunk more over the past several decades for people with only a high school degree and those with some college education than for college graduates, although college graduates experienced a smaller gender wage gap during the entire period (Blau 1998, 130). Still, the most recent data on college graduates suggest that one year after graduation, college-educated women earn about 20 percent less than their male counterparts (Dey and Hill 2007). My own research identified a similar gender earnings gap among young, college-educated workers a few years into their careers (Bobbitt-Zeher 2007).

Parallel Trends

The declines in the gender wage gap parallel dramatic changes in women’s participation in higher education. In 1970, there were only 68 women for every 100 men in college, but by the end of the 1970s, men and women were enrolling in equal numbers (Sum, Fogg, and Harrington 2003, 13). Since then women have significantly outpaced men as enrollees. Women are not only enrolling in college in greater numbers than men, they are also surpassing men in graduating from high school, attending college, and attaining college degrees (see, for example, Freeman 2004). These gender gaps favoring women are expected to widen further over the next decade (Sum, Fogg, and Harrington 2003).

At the same time that women’s involvement in postsecondary education has expanded, fields of study also have seen greater gender integration. For example, in 2001, women received 61 percent of degrees in accounting (as compared to 9 percent in 1970) and earned twenty times more engineering degrees than in 1970 (Freeman 2004, 78). But in spite of the trend toward integration, college majors are still quite segregated by gender (see, for example, England and Li 2006). For example, in 2000–2001, women received 77 percent of education degrees and only 20 percent of engineering degrees (Freeman 2004, 78). Complementing the trend in the gender wage gap, changes in college major segregation vary by decade. College major segregation declined substantially in the 1970s and early 1980s before stagnating throughout the rest of the 1980s and into the 2000s (England and Li 2006; Jacobs 1995). Attributing integrative trends to women’s increasing tendency in the 1970s and early 1980s to enter majors like business instead of traditionally female majors like education, England and Li suggest that desegregation has stagnated since the mid 1980s for two reasons: men have not entered fields with high proportions of women in significant numbers, and many women continue to enter traditionally female majors (2006).

Some studies have implicated gender differences in college majors in the gender wage gap, suggesting that women tend to have lower incomes in part because they major in fields that garner lower financial rewards in the labor market (see, for example, Bradley 2000). Thus men are more concentrated in higher-earning fields, and women in lower-earning fields. While there is debate about whether a field’s relative compensation depends more on its content or its gender composition per se (see Bobbitt-Zeher 2007), gender segregation by field does seem to contribute to gender income differentials. In fact, several studies have found that college major explains between roughly one-quarter to one-half of the gender income gap for college graduates (Daymont and Andrisani 1984; Brown and Corcoran 1997). However, few studies have considered the impact of college major segregation alongside the work-, family-, and aspirations-related factors also known to influence the gender income gap (see Bobbitt-Zeher 2007 for a discussion of these and related factors).

Connecting the Trends

In my research, I wanted to explore the connections between the parallel trends in the declining gender income gap and declining college major segregation. I compared two cohorts of young workers: one of workers who graduated from high school in 1972 and were working in 1979, and a parallel cohort from twenty years later (the class of 1992, who were working in 1999). Data come from the National Longitudinal Study of the High School Class of 1972 and the National Education Longitudinal Study of 1988, two nationally representative datasets. Within both cohorts, I focused on full-time workers working year round, analyzing separately those who had at least a bachelor’s degree, those with less than a bachelor’s degree, and the combined sample of all full-time, year-round workers. I examined the educational, familial, aspirational, and work-related factors that might perpetuate gender income inequality at each point in time and looked for any changes in these influences over time.

I found that during the last decades of the twentieth century, the gender income gap declined for college-educated workers beginning their careers. The ratio of women’s to men’s earnings rose from 0.78 in 1979 to 0.83 in 1999 for workers with college degrees. For those concerned with gender equity, this is an encouraging pattern. Yet while the gender income gap is smaller in 1999 than in 1979, it remains significant. Even in 1999, college-educated women were making about $6,500 less per year than similarly aged college-educated working men.  

When I considered the overall gender income gap across levels of educational attainment, I found that women’s strides in college completion along with changes in their college majors accounted for 14 percent of the decline in the overall gender income gap between 1979 and 1999.  Thus, gendered changes in higher education have helped reduce the gender income gap.  However, examining factors that affect the gender income gap’s persistence at each point in time, I also found that education played a bigger role in perpetuating the gender income gap in 1999 than it did in 1979. About 19 percent of the income gap between college-educated men and women in 1999 could be explained by the gender composition of their college major—nearly twice as much as in 1979, when gender composition in the college major explained 10 percent of the gap. No other single factor was more important in explaining the income gap in 1999, although work-related characteristics like occupation, industry, and economic sector combined to explain a bigger share of the gap (about half). In addition, college major is the only substantial explanatory factor that increased in importance between 1979 and 1999.

Thus even as trends in higher education participation are advantaging women (Buchmann and DiPrete 2006; DiPrete and Buchmann 2006), college majors are playing an increasingly important role in perpetuating lingering income inequality. And while college major integration holds potential for reducing enduring inequalities in earnings among men and women with college degrees, stalling college major integration (see England and Li 2006) may contribute to the continuation of gender income gaps into the twenty-first century.

Conclusion

One should not overstate education’s role in perpetuating earnings inequality between men and women. My analysis suggests that changes in men’s and women’s job placement (for example, in occupation, industry, and sector) hold the most promise for further reducing gender income inequality. But college major does link with occupational choice (Shauman 2006), and gender segregation in higher education plays an increasingly important role in perpetuating income differences by gender. Given that trends toward women’s greater participation in higher education are projected to continue (Sum, Fogg, and Harrington 2003) and small gender income differences tend to grow over careers (Blau and Kahn 2000), it seems prudent to address the role educational gender segregation plays in maintaining gender inequality in contemporary society.

References

Blau, F. D. 1998. Trends in the well-being of American women, 1970-1995. Journal of Economic Literature 36 (1): 112-165.

Blau, F., and L. M. Kahn. 2000. Gender differences in pay. Journal of Economic Perspectives 14 (4): 75-99.

Bobbitt-Zeher, D. 2007. The gender income gap and the role of education. Sociology of Education 80 (1): 1-22.

Bradley, K. 2000. The incorporation of women into higher education: Paradoxical outcomes?  Sociology of Education 73 (1): 1-18.

Brown, C.,  and M. Corcoran. 1997. Sex-based differences in school content and the male–female wage gap. Journal of Labor Economics 15 (3): 431-465.

Buchmann, C., and T. A. DiPrete. 2006. The growing female advantage in college completion:  The role of family background and academic achievement. American Sociological Review 71 (4): 515-541.

Daymont, T. N., and P. J. Andrisani. 1984. Job preferences, college major, and the gender gap in earnings. Journal of Human Resources 19 (3): 408-428.

Dey, J. G., and C. Hill. 2007. Behind the pay gap. Washington, DC:  AAUW Educational Foundation.

DiPrete, T., and C. Buchmann. 2006. The gender-specific trends in the value of education and the emerging gender gap in college completion. Demography 43 (1): 1-24.

England, P., and S. Li. 2006. Desegregation stalled: The changing gender composition of college majors, 1971–2002. Gender and Society 20 (5): 657-677.

Freeman, C. E. 2004. 2004. Trends in educational equity of girls and women: 2004 (NCES 2005-016).  Washington, DC:  National Center for Education Statistics.

Institute for Women’s Policy Research. 2010. The gender wage ratio: Women’s and men’s earnings. IWPR Publication No. C350 (updated). Washington, DC: Institute for Women’s Policy Research.

Jacobs, J. 1995. Gender and academic specialties: Trends among college degree recipients during the 1980s. Sociology of Education 68 (2): 81-98.

Marini, M. M., and P. Fan. 1997. The gender gap in earnings at career entry. American Sociological Review 62 (4): 588-604.

Shauman, K. A.  2006. Occupational sex segregation and the earnings of occupations: What causes the link among college-educated workers? Social Science Research 35:577-619.

Sum, A., N. Fogg, and P. Harrington. 2003. The growing gender gaps in college enrollment and degree attainment in the U.S. and their potential economic and social consequences. With I. Khatiwada, S. Palma, N. Pond, and P. Tobar. Boston: Center for Labor Market Studies. www.brtable.org/pdf/943.pdf.

U.S. Department of Labor, Bureau of Labor Statistics. 2004. Highlights of women’s earnings in 2003. (Report 978.) www.bls.gov/cps/cpswom2003.pdf.