Women are leaving the top ranks of companies at higher rates than ever before — as female employees remain less likely to get promoted into leadership roles in the first place.

For every woman at the director level who gets promoted, two female directors are choosing to leave their company, according to a new McKinsey & Co. and LeanIn.org report. The organizations, which analyzed data from 12 million employees at more than 330 companies, have been tracking the state of female workers since 2015, with the findings published in an annual report.

“Women are just as ambitious as men, but they are leaving their companies at the highest rates we’ve ever seen and at higher rates than men in leadership,” said LeanIn CEO Rachel Thomas. “We really think this could spell disaster for companies.”

Women have long been at a disadvantage in the workplace, but many of those problems have been exacerbated by the COVID-19 pandemic. A lack of affordable child care has contributed to more women leaving the workforce than men in recent years. A gender pay gap, which had been narrowing, also stalled during the pandemic.

Now, those in the highest ranks of their organizations are re-evaluating because of a lack of advancement opportunities, flexibility or unequal treatment, or a combination of these and other factors.

Take Susan Chapman-Hughes, who left her job at a payments company after an 11-year stint. Chapman-Hughes, who ran digital transformation efforts for one of its business units, said the next opportunity she was offered there “did not fit the narrative” she had for herself.

“Every organization cannot give you what you want for the rest of your career,” she said. “You have to be smart enough to chase those desires.”

Currently, only one in four C-suite leaders is a woman, according to the report. That compares to one in 20 for women of color, per the summary.

And for every 100 men promoted to a manager role from entry-level, 87 women are promoted. That number drops to 82 for women of color. Those figures compare to 86 and 85 for all women and women of color in last year’s report.

Carmen Bryant recently quit her position as marketing director at an online job listings company after her brother died of pancreatic cancer.

“I had this epiphany that life is really short, and there’s no reason why I need to be somewhere that is not serving me,” said Bryant, who wanted a more expansive role.

That mind-set helped nudge Bryant, who is Black, to jump to WizeHire, an online hiring platform, where she’s vice president of marketing.

“A lot of women think if they work hard, people will notice and that will be enough,” she said. “The truth of the matter is women have to advocate for themselves. And Black women have to walk a fine line, being careful about how aggressive you are perceived.”

As companies continue tweaking their telecommuting policies after the explosion of remote work brought on by the pandemic, McKinsey and LeanIn found that only one in 10 female employees want to work from the office most of the time. The summary of their report said “many” women call hybrid work schedules a key reason for joining or sticking with an employer.

“Women are not breaking up with work; they are breaking up with companies who are not delivering the work culture and the opportunity and the flexibility that’s so critically important to them,” Thomas said.