A record number of women now hold the top spot at Fortune 500 companies. Of the companies that make up the 2019 Fortune 500 list, released today, 33 have women CEOs.
Not only is it the highest number of women to ever helm Fortune 500 companies at the same time, it's a considerable increase from last year's total — 24 women.
In the last 12 months, Northrop Grumman appointed Kathy Warden as CEO, Land O'Lakes appointed Beth Ford and Best Buy appointed Corie Barry, who will step into her role on June 1.
Williams-Sonoma CEO Laura Alber and Advanced Micro Devices CEO Lisa Su have both occupied their roles for several years now, but since their companies have surpassed the Fortune 500 revenue theshold of $5.575 billion, they are now ranked among the CEOs on this year's prestigious list.
Though considerable gains have been made within the last year, women still make up just 6.6% of CEOs at the companies on Fortune's list. Women of color make up an even smaller percentage of this group.
Mary Winston was appointed interim CEO of Bed Bath & Beyond earlier this week, making her the first black woman to head a Fortune 500 company since Ursula Burns stepped down from her role at Xerox more than two years ago. PepsiCo's Indra Nooyi and PG&E CEO Geisha Williams have both left their roles since their companies appeared on last year's Fortune 500 list.
Utah State University professor Christy Glass tells Fortune that in her research with co-author Alison Cook on gender inequality and race in the workplace, she's seen that "when boards are well-integrated with women, women are much more likely to be appointed CEOs." And, she says, when women are on boards they are also more likely to recruit and promote people of color.
According to data from Fortune, women held 15.7% of board seats at Fortune 500 companies 15 years ago. Today, women hold 25.5% of those seats.
"Our research suggests that when women lead companies at the board rank and as CEOs, [there's] more attention [paid] to equality policies and practices," she says. "So one added bonus of the growth of women directors is that CEOs place more emphasis on recruiting, retaining and advancing people of color."
While progress has been made, women in leadership still face an uphill climb. Fortune notes that women CEOs in the Fortune 500 tend to have shorter stints than their male counterparts — on average, women serve 42 months as CEO, versus 60 months for men.
At the time of Nooyi's departure, Lisa Mann, CEO and founder of Think Marketing, told CNBC's "Power Lunch" that "companies should be embracing their VPs and SVPs who are women and nurturing them to be leaders in business."
If that doesn't happen, both Mann and CNBC contributor Suzy Welch say that more women will continue to leave corporate America to create their own opportunities. "There is an off-ramp of women who want to be in business and have more control and run their own thing," Welch said on CNBC's "Power Lunch."
"If you're going to have pain," Welch said, "then you might as well control it more — and you can do that as an entrepreneur."
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