According to Business Insider magazine, Utah ranks fourth in the nation for having the largest pay gap between men and women working full-time.

The magazine reports:

This map, based on data from the U.S. Census Bureau’s 2012 American Community Survey, shows the gap between the 2012 median earnings for a year-round full-time male worker and a similar female worker, as a percentage of the median female’s earnings.

Utah ranks 46th out of 50 states.

How responsible is Mormonism, the religion of 62% of Utah’s people, for this gender discrepancy?

Before we explore that question let’s take a quick look at what the census study says about women in Utah — and what it doesn’t. I particularly want to point out that this data is not chronicling a divergence in “equal pay for equal work.”

In other words, no one is claiming from this data that women in Utah who are, say, high school history teachers with 22 years of experience are making 42.5% less than male high school history teachers who also have 22 years of experience in the same school system.

But the findings are troubling nonetheless. Women in Utah make 42.5% less income than men. In Wyoming, the nation’s worst offender, the chasm is 56.6%.

What accounts for the persistent gap between women and men, which is clearly worse in some places than in others? Economists point to several reasons:

1) The most significant factor accounting for the wage gap is women’s greater tendency to leave full-time work for years at a time to care for children at home. The long-term effect on American families may be positive, but the long-term effect on women’s earnings is disastrous. One key thing to note in all the discussion this week about equal pay is that the average may be that women earn “77 cents on the dollar” nationwide. However, “single, childless women earn 95 cents for every dollar a single, childless man makes, which is hardly the stuff of campaign slogans.” In other words, American women who never leave the workplace for any length of time have almost achieved wage parity with men.

2) Another cause — one that is less significant in the beginning but can add up over time — is women’s failure to negotiate and renegotiate their salary. Some studies have shown that even when women work longer hours and make fewer errors at work than men, they are less likely to ask for a raise or promotion. And when they do ask, they’re likely to settle for less money than a male employee would. In 2012, the Freakonomics podcast reported that the male advantage disappears when employers make it clear that women are expected to negotiate. The New York Times also reports that it disappears when companies provide employees with hard data on what others are making.

3) Finally, women cluster in careers that pay less than those embraced by men. As The Economist noted this week, men in the United States “are 87% of engineers but only 16% of teachers.” Social work, early childhood education, and visual arts — all fields dominated by women — simply do not pay as well as the STEM fields still dominated by men.

Those three factors help explain the persistence of the wage gap in the United States despite many advances made by women. But having said all that, why are women’s earnings in Utah so much worse than, say, in Vermont?

Because Utah has a higher percentage of stay-at-home mothers. In fact, it’s the highest in the nation, according to one 2007 study.

Utah mothers are also more likely to have larger families, resulting in more years out of the work force: Utah leads the nation in the number of births per woman (2.5 on average), whereas Vermont is the very lowest, with a fertility rate of 1.6.

What is the culpability of Mormonism in creating the wage gap in Utah? Of course it is a significant factor. When nearly two-thirds of the people in a state are members of a religion that has repeatedly and explicitly encouraged mothers to stay out of the work force, it can’t help but have a deleterious effect on women’s earnings.

Less clear from a quantitative standpoint is whether or how Mormonism might play a role in the other two factors. For example, does Mormon culture encourage a meekness in women that might make them reluctant to ask for a raise or a promotion? And does it steer them toward lower-paying careers in “helping” professions such as teaching and nursing?