Sheryl Sandberg, chief operating officer of Facebook, speaks during the World Economic Forum in Davos, Switzerland, on Thursday, Jan. 24, 2013. Photographer: Simon Dawson/Bloomberg

The conventional explanation for why there are so few women in high tech has hinged on a simple statistic: Only about 18 percent of computer science and engineering degrees go to women every year.

Yet tech companies have experts in finance, marketing, sales — not just programming. And women account for nearly 40 percent of all MBA graduates. Moreover, many financial services companies hire equal numbers of men and women at the entry level. So Catalyst, a nonprofit research organization focused on the advancement of women, wanted to figure out if women are faring better on the business side of the fast-growing tech world.

They aren’t.

Among MBA graduates, fewer women than men choose to go into tech-intensive fields, Catalyst found in a report released Thursday. And when women with MBAs do opt in, they tend to start out in lower-paying, lower-level positions than their male counterparts do. They also are significantly more likely to leave — not the workforce, as many assume, but the tech industry itself.

Catalyst analyzed the career paths of nearly 10,000 MBA graduates from 2007 to 2014 in the United States, Canada, Europe and Asia. It found that 53 percent of the women left tech-intensive professions for other work, compared to 31 percent of the men.

“These industries have reputations for being exclusive — the 'brogrammer' culture in high tech, the Old Boys’ Club is really typical in oil and gas, automotive and manufacturing. And it turns out, these reputations are really well deserved,” says Anna Beninger, the report's author and Catalyst’s research director. "The tech industry has some significant culture issues, and it’s really damaging their ability to attract the best talent.”

Companies like Google, Facebook and Twitter are not only male heavy on the tech side, but they have few women in business or in leadership. "Women coming out of business schools, looking to advance their careers, look at these industries and realize they’ll be the only woman in the room," Beninger says. "So they’re looking elsewhere.”

Or, put more bluntly, female MBA graduates see these testosterone-fueled tech cultures, Beninger says, and “they run screaming.” One female technology executive, who has worked for several major tech firms but requested anonymity to speak freely, recalled that in the late 1990s she would see lines in the ladies room at the companies where she worked. "Now they're empty. The women have gone somewhere."

In the report, “High Potentials in Tech-Intensive Industries: The Gender Divide in Business Roles,” Beninger found that women with MBAs felt like outsiders even on the business side of technology companies. In tech, compared with other industries, they were more likely to work on a team with 10 percent or fewer women. They had fewer female supervisors and role models. And they were less likely to say they had a clear sense of how they were being evaluated.

The research not only compared women's experiences across fields, it looked at the difference in outlooks between female and male MBA grads within the same technology sector. The women were more than twice as likely to say that having no role models was a significant barrier to their advancement (18 percent to men's 7 percent). Fewer aspired to the C-suite (84 percent to men’s 97 percent). And they were more likely to downsize their aspirations (37 percent to men's 25 percent).

This expands on what other recent surveys and studies have shown: Corporate cultures, not just education, are a big reason behind the low number of women in high tech. The Center for Talent Innovation, a research think tank, published a report in February which found that U.S. women are 45 percent more likely than their male peers to plan to leave such "lab-coat, hard-hat and geek workplace cultures" within one year.

It doesn't help that some people running tech firms don't think these female MBA graduates could ultimately lead them. CTI's study found that nearly a third of senior leaders — both men and women — in science, technology and engineering fields don't believe a woman would ever reach the top position in their companies.

"Women MBAs work incredibly hard in whatever industry you put them in," says Laura Sherbin, director of research for CTI. "This is not about shying away from hard work. This is more about bias, whether you see it to be conscious or unconscious, that we don't see women in this industry to be intrinsically as capable."

More recently, Kieran Snyder, the CEO of analytics startup Textio, published the results of a survey of women who had left the tech industry. Of the 716 women she queried, 625 said they had no plans to return to the field. Women told her about the discrimination they faced, about being the first person to ever use their company's maternity leave policy, and about how tired they were of being asked to represent the female perspective just because they were the only women around.

Those stories, Snyder says, didn't just come from programmers or industrial engineers, but from women in business jobs at tech companies who had few role models to emulate. "There's this sense of alienation from being the only woman in the room," she says.

But what of Facebook Chief Operating Officer Sheryl Sandberg? Yahoo CEO Marissa Mayer? Meg Whitman, Carly Fiorina, Anne Mulcahy, Marillyn Hewson — all who have served as CEOs of high-power tech companies?

“They are definitely a great face, and it’s very encouraging to see them there,” Beninger says. “But as a statistician, when you look at the full sample, they are definitely outliers.”

In the course of her research, Beninger asked for advice from some successful women in the field. “One said she tells young women to use a black coffee mug, because it doesn’t show lipstick marks. I was floored, but she was dead serious,” Beninger says. “Another highly-placed chief technology officer said she tells young women not to bring notebooks to meetings, because everyone will assume they’re secretaries. That kept happening to her, even as she got more senior."

In the Catalyst report, Beninger noted that male-dominated tech companies can change the dismal gender equation by having top leaders sponsor promising women, by making performance criteria transparent, and by promoting flexible work environments for both men and women. The report found that although 75 percent of the male and female MBA grads they studied had technical backgrounds, only 36 percent chose to return to tech-intensive fields. “The pipeline is leaking both men and women,” Benninger says. “Men want flexibility, too.”

Snyder, who has worked at Amazon and Microsoft in the past, advises women not to assume their requests for more flexibility will be deemed unreasonable. "I’m a single mom, and one thing I got really good at doing was drawing boundaries around my time," she says. She acknowledges, however, that she felt more comfortable doing so because of her seniority. When flexibility is "not a thing that most people you're working with care about," Synder says, "it's easy to not ask the question."

For some women, striking out on their own seems like the better option. Until she had her first child, Desiree Lehrbaum worked in Silicon Valley in what industry observers have dubbed the "pink ghetto" of high-tech firms — that is, their marketing and human resources departments. She left her marketing job to start a consulting firm, Lumen Consulting, doing largely the same work but gaining a measure of control over her schedule by choosing her own projects and setting her own hours.

Advancing in the tech culture, she says, still has a lot to do with subtle factors like being an insider, knowing someone or finding the right boss. “[Leaders] may like a woman and give her tons of work, but will she advance in the same way? It depends,” Lehrbaum says. “And if women find themselves not advancing, figure they’re going to be on the treadmill forever, a lot are going to opt out and find something else. It’s a shame. These companies are vastly underutilizing this amazing pool of talent because they’re caught in such an old paradigm.”

Lehrbaum recalls attending panel discussions with the handful of women who had made it to the top in high tech. Each one had a spouse who either stayed at home or who had a flexible or part-time schedule. “Not one was dual-career, dual-income,” she says. “You got the message that that was the sort of price someone in the family would have to pay to make it.”

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