By Kurtis Alexander and Sarah Ravani, New York Times

SAN FRANCISCO -- Gay affluence may be largely a Hollywood myth, with tired cliches of gays and lesbians living handsomely in chic American cities. But men in same-sex marriages tend to make a good deal more money than households with heterosexual spouses, according to data (pdf) released Monday by the U.S. Department of the Treasury.

The federal agency's first-ever look at the tax returns of same-sex married couples who file jointly shows that gay men had an average household income in 2014 of $176,000 -- 36 percent higher than the $113,000 average for opposite-sex couples. Married males with kids were raking in nearly $275,000.

Women in same-sex marriages had an average household income of $124,000, also higher than the national average for all couples.

The findings -- while providing some of the most revealing information about the nation's little-tracked gay population -- are as much a portrait of the community as they are a look at societal gender norms and biases, experts said, with wrinkles that are both well-understood and still being explored.

The tax returns show gay couples are clustered in metropolitan areas along the coast that generally feature higher-paying jobs, with San Francisco home to the nation's highest concentration of married male couples and Oakland home to the largest concentration of married female couples.

The financial edge of married same-sex couples dramatically fades, though, when their income is compared to those living around them. In fact, female same-sex spouses lose any income advantage over opposite-sex couples within their zip code, the Treasury data show.

M.V. Lee Badgett, a senior scholar at UCLA's Williams Institute, which studies sexual orientation, said women in same-sex relationships are wrestling with the same obstacles that heterosexual women face, not the least of which is the nation's gender-based income disparity.

``The pay gap times two is still an issue for lesbians,'' she said.

The average annual household income for same-sex married women -- $124,000 -- compares to $132,000 for opposite-sex couples living nearby when the figures are weighted by geography.

Children also play into the finances of lesbians, who are four times more likely to be raising kids than their same-sex male counterparts. The time and energy spent raising a family can impede career development and earnings.

``Being a parent, having kids, puts people in a common position, regardless of sexual orientation,'' Badgett said. ``When you compare people who are in the same places, they look more similar.''

Lesbian couples are also more apt to live in smaller cities and suburban areas than same-sex male couples, which reduces access to higher-paying jobs.

The pay of same-sex married men, however, remains slightly higher than that of opposite-sex couples living nearby, the data show. And male couples with children had the highest incomes of any married group.

Experts say that's because of the high cost of private adoption or surrogates, which can be prohibitive for less well-to-do households.

``This is just telling us it's extremely expensive to be a same-sex male couple and become a parent,'' said Martha Olney, an economics professor at the University of California at Berkeley, who raised a son with her same-sex partner. ``If you're a same-sex couple and you're adopting, you're looking at a minimum of $10,000 and a maximum of $30,000 to $50,000.''

The Treasury data counted a total of 183,280 same-sex married couples filing joint tax returns in 2014. That's about a third of 1 percent of all married filers.

The federal government began allowing same-sex couples to file a joint return in 2013, two years before same-sex marriage was legalized on the national level.

Experts say the real number of same-sex married couples is probably higher, since gay marriage wasn't legal in many states at the time of tax filing and some might not have exercised the joint-return option.

To Learn More:

Joint Filing by Same-Sex Couples after Windsor: Characteristics of Married Tax Filers in 2013 and 2014 (by Robin Fisher, Geof Gee and Adam Looney, (Office of Tax Analysis, U.S. Department of Treasury) (pdf)

Equal Employment Opportunity Commission Rules that 1964 Civil Rights Act Protections Apply to Gay Men and Lesbians (by Steve Straehley, AllGov)

Now Some Same-Sex Couples are Told They Have to Marry … to Keep Their Job Benefits (by Noel Brinkerhoff, AllGov)