Numerous studies over the years have purported to explain the alleged wage gap between men and women, but all have suffered from the problems of finding comparable jobs and determining an employer’s level of sexism. A new study by two Harvard University economists, however, manages to eliminate these variables and, in the process, shows that the wage gap can be completely explained by the different choices male and female employees make.
The study, by Valentin Bolotnyy and Natalia Emanuel, examined wage differences between male and female bus and train operators working for the Massachusetts Bay Transit Authority (MBTA) during the 2011 – 2017 period. This was an ideal environment for the study because the union contract covering all these employees is rigidly structured to eliminate practically all subjectivity on the part of MBTA management. All employees receive the same training and start at the same wages. Thereafter, wage increases, promotions, and other benefits are doled out on the basis of seniority, with little managerial discretion allowed. Seniority also is the sole determinant of an employee’s work opportunities, including choice of schedules, routes, vacation days, and overtime hours.
Under such a contract, one would expect men and women to earn about the same amount, yet the researchers found that female MBTA operators still took home only 89 cents for every dollar that male operators made. “The earnings gap persists even when we condition on seniority,” the researchers observed, “allowing us to explain the gap fully by the differences in choices that men and women make when faced with the same choice sets in the workplace.”
The short explanation: “Men take 48% fewer unpaid hours off and work 83% more overtime hours per year than women.” That, of course, adds up to more take-home pay for men. But what explains the difference in hours worked? “Women have greater demand for workplace flexibility and lower demand for overtime work hours than men,” largely because women are responsible for more household and childcare duties than men.
Overtime is a major contributor to the wage gap. Men and women take roughly the same amount of overtime when hours are scheduled in advance, but when hours are scheduled the day of or the day before the shift, men take nearly twice as many hours as women.
Men also take much greater advantage of the flexibility afforded them under the 1993 Family and Medical Leave Act (FMLA) to earn overtime pay. The FMLA was intended to allow employees to take unpaid time off to deal with family or medical emergencies; but at MBTA, where it has become known as the “Friday – Monday Leave Act,” it is used rather indiscriminately to give employees unpaid time off whenever they want it. Bolotnyy and Emanuel found that “male operators exploit FMLA to game the system: by substituting unpaid hours for overtime hours, they actually increase their earnings.” Specifically, if a male operator is scheduled to work a weekend, he is likely to take unpaid time off, where he would only be paid his normal wage, and then work extra overtime hours, where he will earn half again as much, thereby making more money than if he’d worked his original schedule. Women, however, do not take advantage of such opportunities as often.
Do women take less overtime, especially on short notice, because they are less self-interested than men? More likely it is because they simply can’t change their schedules as readily. Even when controlling for seniority, which gives operators first dibs on overtime hours, the economists found that “women value time and flexibility more than men,” particularly if they have children and cannot obtain care for them during overnight and weekend shifts.
“We see women prioritizing schedule convenience more than men in other respects,” they wrote. “As operators move up the seniority ladder and consequently have a greater pool of schedules to pick from, women move away from working weekends, holidays, and split shifts more than men. Women are more likely than men to take less desirable routes … to avoid the less preferable schedules.”
Economist John Phelan summed things up best: “The ‘gender wage gap’ is as real as unicorns and has been killed more times than [Halloween character] Michael Myers.”