If you want to be the CEO of a powerful company, choosing the right college major is an important place to start.

We took a look at the leaders of the top 11 companies in this year’s Fortune 500, and by and large, they each majored in a field directly related to industry of their future employer. And nearly all of the CEOs obtained post-graduate education after getting their bachelor’s degree.

Here are the college degrees held by some of America’s most powerful CEOs.

Related video: Is College Education Dead?

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Steven Collis — AmerisourceBergen

AmerisourceBergen is worth $17.31 billion.

B.S. in commerce — University of the Witwatersrand

Honors bachelor of commerce — University of the Witwatersrand

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James Hackett — Ford Motor Company

Ford Motor Company is worth $46.65 billion.

B.S. in finance — University of Michigan

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Randall Stephenson — AT&T

AT&T is worth $212.54 billion.

B.S. in accounting — University of Central Oklahoma

Master of Accountancy — University of Oklahoma

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Mary Barra — General Motors

General Motors is worth $61.64 billion.

B.S. in electrical engineering — General Motors Institute

M.B.A. — Stanford University

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Larry Merlo — CVS Health

CVS Health Corp. is worth $71.18 billion.

B.S. in pharmacy — University of Pittsburgh

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David Wichmann — UnitedHealth Group

UnitedHealth Group is worth $202.57 billion.

B.S. in accounting — Illinois State University

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John Hammergren — McKesson

McKesson is worth $29.41 billion.

B.A. in business administration — University of Minnesota

M.B.A. — Xavier University

AP Photo/Richard Drew

Darren Woods — ExxonMobil

ExxonMobil is worth $339.55 billion.

B.S. in electrical engineering — Texas A&M University

M.B.A. — Northwestern University

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Tim Cook — Apple

Apple is worth $871.85 billion.

B.S. in industrial engineering — Auburn University

M.B.A. — Duke University

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Warren Buffett — Berkshire Hathaway

Berkshire Hathaway is worth $443.69 billion.

B.S. in business administration — University of Nebraska

M.S. in economics — Columbia University

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Doug McMillon — Walmart

Walmart is worth $228.28 billion.

B.S. in business administration — University of Arkansas

M.B.A. in finance — University of Tulsa