At the beginning of this year, the Fortune 500 crossed a milestone: for the first time in history, women ran more than 10% of the businesses on the list of America's largest public companies. Five months later, the 69th annual Fortune 500 ranking is out, and those CEOs are proving their staying power. Women run 10.4% of companies on the Fortune 500 this year.

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The Fortune 500 ranks the largest U.S. public companies by revenue; the 500 companies on the list represent $18 trillion in revenue, more than two-thirds of U.S. GDP. The list is a microcosm for American business writ large, so the share of firms led by female CEOs sheds light on gender diversity in executive leadership beyond just this elite cohort.

This year, 52 companies out of 500 are led by female CEOs. That's an 18% increase from 44 this time last year. Twelve CEOs were hired to their jobs within the past year, a rate that reflects the rapid pace of executive turnover post-pandemic.

View this interactive chart on Fortune.com

The rise of female CEOs signals an understanding among companies and boards that female and diverse leaders are an asset at this particular moment. As Julie Sweet, the CEO of Accenture, says she advises corporate leaders: "The era of A.I. is requiring companies to reinvent every aspect—we call it total enterprise reinvention," she says. Diverse leaders, who also tend to hire more diverse teams that support business innovation, are especially well-suited to that challenge. "Diverse leaders have had to continuously reinvent and adapt at a personal level throughout their careers. They're resilient, adaptable, and have to be pioneers."

Female CEOs join or exit the group of Fortune 500 leaders one of two ways: first, an existing Fortune 500 company hires, fires, or retires a new chief executive; secondly, a company's revenue boosts it onto the Fortune 500 or kicks it off. (The revenue threshold for this year's Fortune 500 is $7.2 billion.)

Several of the 12 new female chiefs this year were internal hires promoted to the CEO job within the past year, including Cummins CEO Jennifer Rumsey, American Electric Power CEO Julia A. Sloat, Reliance Steel & Aluminum CEO Karla R. Lewis, ADP CEO Maria Black, Parker-Hannifin CEO Jennifer A. Parmentier, Fidelity National Information Services CEO Stephanie L. Ferris, and Opendoor CEO Carrie Wheeler. Becoming a Fortune 500 CEO is a specific goal some executives set for themselves; for others, it's a byproduct of their career trajectories. Wheeler was CFO when Opendoor, a real estate technology company, joined the Fortune 500 for the first time last year. She was promoted to CEO in December. "I'm just focused primarily on executing—but it's lovely to be on the list. The focus is just making sure that we're driving the business forward."