This year was touted as the year of women in politics in the United States, but in the business world, female bosses remain few and far between.
And some warn the situation is unlikely to improve with men unwilling to play the role of mentor to younger female colleagues in the era of the #MeToo movement, which has heightened awareness of sexual abuse and inappropriate behavior in the workplace.
The departure in September of India's Indra Nooyi as head of PepsiCo after more than a decade in the job has only reinforced a trend that has been growing for the past two years: the decline in the number of women CEOs even as debate about the need for equality in the workplace rages, and amid increasing calls for women to break through the "glass ceiling."
Recently, a number of prominent women have left their posts as company heads, including Denise Morrison of Campbell Soup, Margo Georgiadis of Mattel, Sherilyn McCoy of Avon, Meg Whitman of Hewlett-Packard, Ursula Burns of Xerox, and Ellen Kullman of Dupont.
All of them have been replaced by men, a blow for diversity since fewer than five percent of leaders of the S&P 500 largest enterprises are now women, down from 5.4 percent in 2017.
"We are going in the wrong direction," said Lorraine Hariton, whose NGO Catalysts advocates for women in senior positions.
"Women have gotten into entry-level positions very successfully, and then they get to middle management, and things stall out," she said. "Women still today are not reaching the top, particularly women of color."
Dismissing the idea that the glass ceiling is down to women's decision to focus on family rather than career, experts lay the blame more on deep-rooted cliches.
Hariton said her group's research "shows that the stereotype that men 'take charge' and women 'take care' puts women leaders in a double bind and can potentially undermine their leadership and career and advancement options."
"Women suffer 'Goldilocks' syndrome: they are judged as being too hard, too soft, and never just right for the job," she said.
"Women are held to higher ethical standards and punished more harshly after ethical violations than are men," said Vanderbilt University professor Jessica Kennedy.
"In short, women face higher standards and have more to prove than men do," she said
Millennial men not so open minded
Women who aim high in business often find they are not invited to important meetings or to after-work gatherings, both places where important connections are made, experts say.
This "culture of exclusion" may get even worse because of the #MeToo movement, because some men worry "that a compliment to their young mentee is likely to actually trigger accusations of sexual harassment," said Kennedy.
"Nothing much happens without sponsorship," said Hariton, noting that a mentor or sponsor shares vital contacts, gives advice and pushes for their protege's advancement.
Even though the number of women in managerial positions has risen in the past decade, many are stuck in mid-level positions like head of human resources, or the legal or financial director of their company, according to Pew Research. Very few rise as high as chief operating officer, the launchpad to the CEO post.
On the other hand, researchers have found that it is not uncommon for a woman to be offered the helm of a company that is already in trouble, a "glass cliff" post she is more likely to accept in a bid to prove herself even if the chances of success are low.
Christy Glass, a professor at the University of Utah, said women are also seen as being better at breaking bad news than men.
She cited the case of Mary Barra, who was named head of General Motors in February 2014, several days before the car maker revealed that its faulty ignition switch was linked to 124 deaths.
Hariton said that to change the dynamic, more women are needed on companies' boards of directors, which are responsible for appointing the head of a firm.
"Eighty percent of board seats at S&P 500 companies are primarily men," said Hariton. "So the lens by which women are being evaluated is a white, male lens."
A recent California law forces publicly listed companies based in the state to appoint at least one woman to their board by the end of 2019, and two or three by the end of 2021.
Kennedy said quotas had been made necessary because even though young men of the "millennial" generation—aged between 17 and 35—were more supportive of sexual equality than their forebears, they also worry that it could impinge on their own career opportunities.
Some large US corporations, such as American Express, Best Buy and Ralph Lauren, have recently signed up to ParityPlegde, in which members pledge to look at least one female candidate when a job position opens up.
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