06/25/2014 04:08 pm ET Updated Aug 25, 2014

A New Theory for Why Women Earn Less

Thomas Barwick via Getty Images

Picture this: Your manager assigns you a challenging new project, and you log countless hours after everyone else has left the office in order to get it done before the deadline.

When raise and bonus time rolls around, your boss remembers how overworked you were -- and rewards you for the effort.

Wouldn't that feel good?

Based on new research, this scenario may be more common for men than women -- and could offer a new explanation for the wage gap between sexes.

RELATED: What Are Your 'High-Earning Years'? A Guide to Your Pay in Your 20s, 30s and 40s

In their paper, sociology professors Youngjoo Cha and Kim A. Weeden suggest the gap has persisted for so many years because men are more willing to be overworked than woman -- and are compensated for it.

Setting out to prove their hypothesis, Cha and Weeden reviewed 30 years of data from the Census Bureau and Bureau of Labor Statistics' Current Population Survey. They found that in 1979, women earned 70% of men's salaries. By 1991, it increased to 75%, and then remained relatively stable at 76% from the late '90s through 2009.

RELATED: Is This the Answer to Closing the Gender Wage Gap? 

The "overworking" trend followed an upward trajectory during the same time period. In the early 1980s, 13% of men and just 3% of women worked 50 hours a week or more. Fast-forward to 2000: 19% of men and 7% of women worked 50 hours or more. The researchers assert that over time, employers started to expect more hours of work from employees, but were willing to pay a premium for it -- which is why men have consistently earned more.

Cha and Weeden estimate that the "overwork effect" has been significant enough to counteract wage-equalizing factors, such as women earning more college degrees than men.

So, why do fewer women embrace long hours like their male counterparts? The researchers suggest it's because women are still expected to shoulder most of the burden for housework and childcare. "[E]ssentialist beliefs about female caregiving continue to be a dominant cultural ideology even among people who endorse gender egalitarianism," write Cha and Weeden.

Still, if you're paid less than your male colleagues, you don't have to suffer in silence. Start by reading our guide to getting paid what you're worth or our how-to on asking for a raise.

This post originally appeared on LearnVest.

More From LearnVest
The Other Big Gender Gap?
30 Smart Career Moves You Should Make by 30
Real Moms, Real Work-Life Balance: What It Looks Like

LearnVest is a program for your money. Read our stories, use our tools and talk to a Planner about getting a financial plan designed for you.

LearnVest Planning Services is a registered investment adviser and subsidiary of LearnVest, Inc. that provides financial plans for its clients. Information shown is for illustrative purposes only and is not intended as investment, legal or tax planning advice. Please consult a financial adviser, attorney or tax specialist for advice specific to your financial situation. LearnVest Planning Services and any third parties listed in this message are separate and unaffiliated and are not responsible for each other's products, services or policies.