The U.S. Commerce Department’s Economics and Statistics Administration has issued the second in a series of reports on science, technology, engineering and mathematics (STEM) jobs and higher education.

As expected, the report “Women in STEM: A Gender Gap to Innovation” finds there are fewer women than men in STEM jobs and attaining degrees in STEM fields. That’s true despite the fact the wage premium for women in STEM jobs is higher than that for men and that there’s greater income parity between genders in STEM fields than there is in the employment market as a whole.

While women make up 48 percent of the U.S. workforce, only 24 percent have STEM jobs. During the past decade, this underrepresentation has remained fairly constant, even as women’s share of the college-educated workforce has increased.

Women with STEM jobs, however, earned 33 percent more than women in non-STEM jobs in 2009, exceeding the 25 percent earnings premium for men in STEM. Women in STEM also experience a smaller gender wage gap than their counterparts in other fields.

“We haven’t done as well as we could to encourage young people to go into STEM jobs – particularly women – which inhibits American innovation,” acting Secretary of Commerce Rebecca Blank said in a statement. “Closing the gender gap in STEM degrees will boost the number of Americans in STEM jobs, and that will enhance U.S. innovation and sharpen our global competitiveness.”

Women who do get STEM degrees are more likely to enter jobs in fields like education or healthcare, the report finds. And while more women choose to major in math than men – nearly 10 percent versus 5.7 percent – most men with STEM majors select engineering degrees. Engineers are the most male-dominated STEM occupational group but also the one with the smallest gender wage gap.

Several possible factors contribute to the discrepancy of women and men in STEM jobs, including a lack of female role models, gender stereotyping, and less family-friendly flexibility in the STEM fields.