Becoming a CEO takes a combination of determination, strong managerial skills and a hunger for growth. But a surprising factor could statistically determine your chances of ascending to the top post — where you previously worked.

According to data from Santa Clara University, between 1992 and 2010, more than 20% of CEOs at S&P 1500 companies had previously worked at one of just 36 high-achieving companies. Colloquially known as “CEO factories,” these competitive firms are a breeding ground for future top executives.

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In a recent study, OnDeck used LinkedIn data to determine which companies stand above the rest when it comes to producing CEOs. Not surprisingly, the top five are management consulting firms — and McKinsey & Company tops the list. More than 7% of McKinsey employees go on to be CEOs. Bain & Company, Boston Consulting Group, Kearney and Oliver Wyman round out the top five.

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The National Football League follows these top consulting firms, with nearly 5% of its former employees going on to become CEOs — not surprising considering how many former athletes found and lead companies post-retirement.

Goldman Sachs, Procter & Gamble and Porsche Cars North America also made the top 20. Read on to see the full list of the top 20 CEO factories.

Image Credit: OnDeck

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