A new global World Bank study indicates that while lesbians earn more than heterosexual women, gay men earn less than heterosexual men. In the UK, for example, lesbians make 8 cents more an hour than straight women—that number goes up to 20 cents an hour in the U.S.  On the flip side, gay men earn five cents less an hour in Great Britain—and up to 12 cents an hour less in Canada.

Lead researcher Dr. Nick Drydakis attributes the increase to certain lifestyle choices that can make gay women assets in the workforce. “Lesbians may realize early in life that they will not marry into a traditional household," and so might stay in school longer, choose a profession with more earning power, or opt for a male-dominated career path where salaries are better. These choices “differ from those they would have made had they adopted traditional gender-based household specialization roles,” the study reports.

For gay men, however, Drydakis sees a clearer link to discrimination. “The labor market values gay men’s characteristics less than those of heterosexual men, and the difference in earnings is attributable to the failure of gay men to conform to traditional gender roles,” the report said. “Studies suggest that firms that are biased against gay men consistently discriminate against them, and that the gap in gay men’s earnings relative to heterosexual men is directly related to the strength of the firm’s bias against gay men.”

Discrimination against gays and lesbians appears more pronounced in fields dominated by one gender or the other—say, construction for men, or nursing for women. The study also found that gay employees are more likely to report harassment, unfair work condition and job dissatisfaction than heterosexual workers.

Less than 20% of countries included in the report have nationwide workplace protections based on sexual orientation—including the United States.