Female CEOs may be few and far between, making up less than 5 percent of CEOs in the S&P 500, but history shows they've been able to generate big returns for investors.
Of the 24 female CEOs in the S&P 500, 13 have led their companies' stocks to outperform the index in terms of cumulative total returns during their tenures. Some have managed to produce triple- and even quadruple-digit percentage gains.
The average year-to-date return from the 24 female-run companies was over 12 percent as of Friday's close, according to S&P Global Market Intelligence, which has made it a mission to promote gender equality through its parent company S&P Global and the #ChangePays initiative. For comparison, the average year-to-date return for male-run S&P 500 companies was around 11 percent.
Yet, even with these gains, the combined market cap of S&P 500 companies with female CEOs totals just over $1 trillion, while the same statistic for male-run companies exceeds $24 trillion.
To make matters more complicated for female CEO hopefuls, the percentage of female CEO appointments at S&P 500 companies has actually dropped in the last decade, averaging less than 6 percent in the last four years, according to Katie Darden, associate director of financial institutions research at S&P Global Market Intelligence.
"What really hit home as I was doing this analysis was just how little data we had to work with," Darden said in a phone interview, highlighting her never-before-published data set provided exclusively to CNBC. "We were dealing with such small numbers of female CEO announcements. That became kind of the main takeaway to me."
Analysis based on data compiled May 17, 2018. Source: S&P Capital IQ, an offering of S&P Global Market Intelligence.