The worlds of finance and big business are notoriously dominated by middle-aged men. But recent research suggests that this may not be for the usually suspected reason — a glass ceiling molded from male prejudice. The research, by Marianne Bertrand, a professor of economics at the University of Chicago Booth School of Business, and two Harvard economics professors, Claudia Goldin and Lawrence F. Katz, provides a statistical explanation: women with children fall behind because they work less, the study says.
Dynamics of the Gender Gap for Young Professionals in the Financial and Corporate Sectors (pdf)
We identify three primary proximate factors that can explain the large and rising gender gap in earnings: (1) a modest male advantage in training prior to MBA graduation combined with rising labor market returns with post-MBA experience to such training; (2) gender differences in career interruptions combined with large earnings losses associated with any career interruption (of six or more months); and (3) growing gender differences in weekly hours worked with years since MBA. Differential changes by sex in labor market activity in the period surrounding a first birth play a key role in this process. The presence of children is associated with less accumulation of job experience, more career interruptions, and shorter work hours for female MBAs but not for male MBAs.