Between 1980 and 2010, the proportion of American women who were married declined from 74 percent to 56 percent. There are plenty of trends during that 30-year span that can help explain the shift in women’s decisions to marry or not: increasing college attendance, growing labor-force participation, increasing rates of incarceration, and changing cultural norms, to name a few. A new study suggests that as their wages increase relative to men’s, female workers become less likely to marry.

A recent study takes a look at the shift in terms of economic incentives and finds that while factors such as increasing employment options and the growing ability for women to choose when or if they have children have certainly affected marriage choices, a shift in women’s wages may be among the most significant factors influencing the decision to pass up on marriage.

In a recent paper, Na’ama Shenhav, a Ph.D. candidate at U.C. Davis, estimates that as much as 20 percent of the decline in the marriage rate over the past 30 years is attributable to women’s growing wages. More specifically, it’s the increase of women’s wages relative to their potential mates and the growing importance of women’s wages to overall household income that have contributed to women’s decisions to delay or forgo marriage. The idea is that for many women, especially those on the lower end of the economic ladder, higher earnings allow them to be less financially reliant on others for things such as rent, groceries, utilities, or other basic necessities. That means that the choice to marry becomes less about financial need and more about other things, like love, social norms, religion, or the desire to start a family.

Talking about women’s wage growth at a time where progress on the gender-wage gap has been largely stagnant—it has remained steady for the past decade or so—can seem odd. But overall, the average weekly earnings of women who worked full-time have increased by about 30 percent since 1980. Men’s and women’s wages actually converged quite a bit between 1980 and 2010, a period when many men saw declining wages as low-skill jobs evaporated, computers came to dominate the workplace, and women graduated from college at higher rates and increased their share of high-skill positions. Today, women on average make about 80 percent of what men make; in 1980, this figure was closer to 65 percent.

Why are more women opting out of marrying? Now, they have less of a financial incentive: The increases in their earnings relative to men’s mean that getting married doesn’t provide quite the same opportunity to improve one’s economic status in the way that it once did. Shenhav finds that for every 10 percent increase in women’s wages relative to men’s (roughly the size of the increase between 1980 and 2010), there’s a 5.3 percentage-point decline in the probability that any given woman will get married. Increased wages mean that women become likely to work more hours (since each hour of work becomes more lucrative) and to be financially independent.

This increase in wages also changes the calculus for women who do decide to marry, leading them to shift away from “less-desirable matches,” as the study puts it. Shenhav finds that wage growth relative to men makes women more likely to marry a man with a higher level of education and less likely to marry one whose education level falls below hers. It also makes women more likely to marry a man who is either the same age or younger, instead of marrying a man who is older.

Does this all mean that women who earn more, in general, are less likely to get married? Not quite. Shenhav’s findings are all about relative wages, and earnings convergence between men and women remains elusive in some of the highest-paying fields. In fact, marriage is the province of the wealthy: Upper-income Americans are more likely to be married than their lower-income peers, and the rise of assortative mating means that more than ever, educated well-off people are intermarrying and staying rich, while poor people are intermarrying, and pretty much staying poor.

Forgoing marriage in favor of economic independence has both positive and negative consequences. While higher wages can mean women are less likely to choose mates with lower education levels and may feel less pressure to marry for the sake of financial security, the ones who live on their own can also find themselves struggling to make ends meet, since overall wage gains are in many cases still not swift enough to keep up with escalating prices, and because two incomes are usually more helpful than one. (Though marriage alone might not solve this problem: Recent research has also shown that despite a push from conservative politicians, marriage also hasn’t proven itself key to eradicating poverty.)

While the consequences of a declining marriage rate may still be murky, one thing seems pretty certain: Giving women more opportunities to work and paying them fair wages for that work provides them options that previous generations of women never had.