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Family Obligations Widen Gender-Pay Gap, Research Suggests

Economists found women with family obligations volunteered for less overtime

A woman and her children sitting at a table with a laptop and a teddy bear.

Women's choices and priorities account for much of the gender-pay gap, new research suggests. But that may not be the whole story, given that family caregiving obligations still fall disproportionately to women.

A paper by Harvard University economists Valentin Bolotnyy and Natalia Emanuel, "Why Do Women Earn Less Than Men? Evidence from Bus and Train Operators," examined seven years of data from 3,011 full-time workers at the Massachusetts Bay Transportation Authority.

The agency operates under a collectively bargained contract that sets uniform hourly wages. Employees are promoted based on seniority, and male and female workers have the same options for scheduling, routes, vacation and overtime.

"Even in a unionized environment where work tasks are similar, hourly wages are identical, and tenure dictates promotions, female workers earn $0.89 on the male-worker dollar" in weekly earnings, the researchers found.

To explain why, Bolotnyy and Emanuel looked at hours worked by employees from 2011 to 2017 and considered workers' sex, age, tenure and whether they were married or had dependents. They found that:

  • Male train and bus operators worked about 83 percent more overtime hours than their female colleagues and were twice as likely to accept an overtime shift on short notice.
  • About half as many women as men took overtime when it was available.

Since overtime work pays time and a half above regular wages, these choices had a significant effect on earnings.

In addition, the study showed that:

  • Male bus and train operators took 48 percent fewer unpaid hours off under the Family and Medical Leave Act (FMLA) each year.
  • Female employees were disproportionately willing to take less-preferable routes if it meant working fewer nights, weekends and holidays.

Parenting amplified the difference in priorities for male and female employees. Fathers wanted the extra cash from overtime more than their colleagues without children, and mothers wanted more time off. These choices were more pronounced among single parents. Unmarried mothers took 59 percent less last-minute overtime than did unmarried fathers.

"Women are less likely than men to game the scheduling system by trading off work hours at regular wages for overtime hours at premium wages," the researchers also found.

"Overall, women, especially single women with children, value both time and the ability to avoid unplanned work much more than men," probably due to a combination of personal preferences and child caregiving responsibilities, Bolotnyy and Emanuel suggested.

The findings indicate that "some policies that increase workplace flexibility, like shift swapping, can reduce the gender earnings gap and disproportionately increase the well-being of female workers," the researchers explained. "Increasing the predictability of overtime opportunities along with schedule flexibility can help women work more hours and reduce the earnings gap."

"Taking time away from the workforce or cutting back hours, both more common scenarios for mothers than fathers, hurts earnings," according to a fall 2018 report by the American Association of University Women (AAUW), a nonprofit organization that promotes equity and education for women and girls. "Many employers and industries still prioritize long, continuous, traditional work hours rather than flexible schedules, a preference that tends to put women with children at a disadvantage."

[SHRM members-only toolkit: Managing Pay Equity]

Same Job, Same Level, Same Pay?

While employers should critically examine their compensation practices to find and correct pay inequities not based on legitimate considerations, recent studies of U.S. workers' earnings don't reveal systemic discrimination by employers against women performing the same jobs—and working the same hours—as men.

Earlier this year, for instance, research by pay consultancy Korn Ferry showed that women in the U.S. earn 17.6 percent less than men on average. But based on data from more than 1.3 million employees at 777 companies, that gap virtually disappears when analyzing men and women who work at the same level at the same company and perform the same function.


Similarly, compensation data and software firm PayScale found that when factors such as experience, industry and job level were taken into account, women earn 97.8 cents for every dollar earned by their male peers for doing the same work, based on the firm's survey of more than 2 million U.S. employees polled through February 2018. 

Looking at pay for men and women overall, however, women on average earned 77.9 cents for every dollar earned by men.

A Societal Problem

A new report from the Institute for Women's Policy Research (IWPR), which supports policy research on gender-related issues, shows that taking a midcareer break of a year or more remains a common experience for women but unusual for men. Also, jobs that women are more apt to hold pay less than jobs more commonly held by men.

The study, Still a Man's Labor Market: The Slowly Narrowing Gender Wage Gap, found that:

  • Female workers overall faced a wage gap of 51 percent in the 2001-15 period—a much wider gap than studies that focus just on full-time, year-round workers indicate.
  • While the long-term earnings gap has narrowed significantly since 1968, progress has slowed in the last 15 years.

The authors used data from the government-sponsored Panel Study on Income Dynamics, a multiyear dataset that follows more than 7,000 U.S. households. They compared data on all women and men with some earnings during the study period, including those who worked part-time or for part of a year and had years of not working.

"Much ink has been spilled debating whether the commonly cited measure of the wage gap—that women earn 80 cents for every dollar earned by a man—is an exaggeration due to occupational differences or so-called 'women's choices,' but our analysis finds that we have actually been underestimating the extent of pay inequality in the labor market," said IWPR president and report co-author Heidi Hartmann.

Among the report's findings and recommendations:

  • The penalties of taking time out of the labor force are high—and increasing. Women who took just one year off from work had annual earnings that were 39 percent lower than women who worked all 15 years between 2001 and 2015.
  • Improving access to paid leave and affordable child care is critical. Forty-three percent of female workers had at least one year with no earnings, nearly twice the rate of men.

Hartmann called for strengthening enforcement of equal employment opportunity policies and Title IX in education to help women enter higher-paying fields and occupations.

"There's also evidence that even the most accomplished professional women may not negotiate their salary as aggressively as men do," wrote AAUW's CEO Kim Churches. "And that can have a snowball effect on earnings over the long haul, since employers often base people's pay on their previous compensation."

Legislative Agenda

Existing laws requiring equal pay for equal work include the Equal Pay Act (1963) and Title VII of the Civil Rights Act (1964), while the Lilly Ledbetter Fair Pay Act (2009) created the possibility that actions from years ago can lead to new discrimination claims.

Among the proposed bills before Congress, the Paycheck Fairness Act would limit employer defenses for pay differences between men and women in similar positions to factors such as education, training or experience, and impose additional civil penalties on large employers for violating the law. Another proposal would prohibit employers from asking prospective employees for their salary history before making a job offer. Meanwhile, more states are passing legislation to address compensation equity.

Related SHRM Articles:

To Improve Gender Equality, Help Men Take Parental Leave, SHRM Online, January 2019

Year End Is Prime Time for a Pay-Equity Review, SHRM Online, December 2018

Close the Gender Pay Gap with Career Parity, SHRM Online, April 2018

SHRM Issues Policy Statement on Compensation Equity, SHRM Online, April 2018

Why Pay Equity Keeps Getting More Complicated, SHRM Online, March 2018

[Visit SHRM's resource centers for Paid Time Off and Pay Equity]


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