Women face a wage gap at every point in their careers, a gap that gets worse as they age and progress through their work lives.
In 2021, the most recent year for which federal data is available, women working full-time in the U.S. were paid 84 cents for every dollar paid to a man, the National Women's Law Center reports.
The gap is even wider when we include women working part-time: Pew Research Center estimates that all women, regardless of the hours they worked, earned an average of 82% of what men made in 2022.
This difference in earnings is perhaps the most obvious once women hit their 30s, which is also when the gap begins to widen.
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Things start to diverge when women are between the ages of 35 and 44, a new analysis from Pew Research Center has found. In 2022, women between the ages of 25 and 34 earned about 92% as much as the men in their age group, while women ages 35 to 44 earned just 83% as much as men their age.
This gap persists even as women are outpacing men in college graduation and enrollment rates — in fact, Rakesh Kochhar, a senior researcher at Pew, found that the gap between women and men with a college degree is not any narrower than the one between women and men without a college degree.
It continues to widen even as women near retirement, as women between the ages of 55 and 64 earn a mere 79% of what men their age make — a troubling trend that hasn't budged in "at least four decades," Kochhar writes.
More than the 'motherhood penalty'
It's no coincidence that the pay gap gets worse around the same time women are more likely to become parents and have young children at home. Last year, 66% of working women ages 35 to 44 had at least one child at home, compared to just 39% of women ages 45 to 54, Kochhar found.
But the explanation for why progress toward narrowing the pay gap stalls once women enter their mid-30s extends beyond the so-called "motherhood penalty."
While it's true that mothers of young children leave the workforce or reduce their hours at higher rates than fathers, the effect this has on women's earnings is typically modest or short-lived, Kochhar writes.
Men, however, tend to work longer hours and receive a bonus when they have children: This "fatherhood premium" has a more immediate, significant impact on the wage gap, Lauren Pasquarella Daley, the leader of Catalyst's women and the future of work initiative, says, as it allows men to move into more competitive, higher-paying roles at the same time women's careers are often interrupted.
Kochhar's research re-affirms this phenomenon: "Among women with similar levels of education, there is little gap in the earnings of mothers and non-mothers," he explains. "However, fathers earn more than other workers, including other men without children at home, regardless of education level."
There are other factors outside of parenthood causing the wage gap to widen for women in their 30s, experts point out, including the increased caregiving responsibilities outside of parenting and unpaid domestic labor more women take on in adulthood, which cuts into their work hours.
"It is still often the woman who takes time off from their job to be a caretaker or manage the household, which, in turn, can exacerbate burnout and depress her earnings," says Jessica Ramey Stender, the policy director and deputy legal director at Equal Rights Advocates, a legal and advocacy nonprofit.
Women are also promoted less than men, which means they are missing out on "critical opportunities" to grow their salaries during their "prime earning years," Daley explains. Experiencing early wage discrimination has a "compounding effect" that can hurt women's earnings potential for years to come, she adds.
Sponsorship can help close the wage gap, especially for women of color, past research from Payscale has shown — but white men tend to receive and benefit more from sponsorship opportunities.
"Young women need people who can advocate for them behind closed doors and recommend them for promotions," Daley says. "That can make all the difference in their career development and, in turn, in their earnings."
The pay gap doesn't just hurt women's paychecks
The loss of 16 cents on the dollar adds up for women and their families over a lifetime, translating into nearly $10,000 less per year in median earnings, per the NWLC's calculations.
Since more single-parent households are headed by women, persistent income inequality for working moms means higher rates of poverty across the U.S.
Lower lifetime earnings also make it harder for women to save for retirement. Assuming a woman and her male colleague both begin working full-time at age 20, the wage gap means a woman would have to work until she is 68 to be paid what a man earns by age 60, the NWLC estimates.
What's more, the gender wage gap takes a toll on women's mental health: A 2016 study from Columbia University found that when women make less money than their male counterparts, they're 2.4 times more likely to experience depression and four times more likely to have anxiety.
"It's not just the dollar amount, it's the perception," Tetyana Shippee, a social gerontologist at the University of Minnesota, explains. "It's the sense of knowing that you are getting less than what you deserve relative to your peers despite how hard you are working, because of forces outside of your control."
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