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Here’s What the Highest-Paid Female CEOs Have In Common

June 20, 2017, 6:52 PM UTC

In case girls need another reason to learn to code: Consider the fact that the four highest-paid female CEOs in the Fortune 500 all run tech companies.

Based on an analysis by board and executive data provider Equilar, the highest-paid U.S. female chief in 2016 was Safra Catz, co-CEO of software maker Oracle (ORCL). HPE (HPE) CEO Meg Whitman, (IBM) CEO Ginni Rometty, and former Yahoo (YHOO) CEO Marissa Mayer (who left the company this month) round out the top four. The fifth—Indra Nooyi—while not a tech CEO per se, holds bachelor’s degrees in physics, chemistry, and mathematics.

Most of the other women represented in the top ten are quants: General Motors’ (GM) Mary Barra is an electrical engineer by training, Lockheed Martin’s (LMT) Marillyn Hewson studied business as an undergrad, and Mondelez’s (MDLZ) Irene Rosenfeld has a PhD in marketing and statistics. The notable exception is General Dynamics’ (GD) Phebe Novakovic, whose academic background is in government and German.

It’s not terribly surprising that the highest-earning women have STEM backgrounds. According to career reviews site Glassdoor, the fields of study with the highest returns are computer science and various types of engineering (electrical, mechanical, chemical industrial).

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On average, the top female CEOs made more than their male counterparts in 2016. According to Equilar, the median total compensation for the nine highest-paid women was $21.2 million in 2016, compared to a median $14.4 million for the 92 male CEOs.

While this is somewhat encouraging news, it’s important to keep in mind that the sample size for women is much, much smaller than it is for men: just 6.4% of Fortune 500 chiefs are female. And while that number has increased nearly 50% since last year—it jumped from 21 to 32—the future isn’t exactly looking bright: The number of women entering STEM fields has actually decreased since the 1980s.