Want a billion-dollar career? Choose this degree

Hoping for that seven-figure annual salary? Well, according to the latest survey, the solution lies in whether your adolescent self picked the right degree.

Engineering is the most popular degree among the world's top 100 billionaires, according to a study by Approved Index, a UK-based business-to-business platform, with more than a fifth (22 percent) having studied this course at university level -- including Google's co-founder, Larry Page.

Ulrich Baumgarten | Ulrich Baumgarten | Getty Images

By compiling data from the world's top 100 billionaires - using Forbes 2015 list -- Approved Index then researched into which degrees were chosen by the most successful business-people.

One surprising factor is that nine percent chose an arts degree, compared to the six billionaires, who opted for either a science, mathematics or law program (2 percent each). Meanwhile, 12 billionaires chose a business degree, while 8 percent studied economics and 3 percent chose finance.

In terms of where their future careers ended up, 19 percent generated their wealth in the tech sector, 15 percent in retail, including the Walton family who are behind Wal-Mart's success.

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Who's in Forbes' top billionaires list?

No degree, no problem

Not an engineering expert? Not a problem. While 68 of the top 100 billionaires graduated with a tertiary level degree; 32 did not. The average wealth for those who didn't study -- or dropped out -- comes to $24.03 billion on average, with engineering being the only degree that generates a higher wealth of $25.77 billion on average.

Some of the world's most celebrated and affluent business-people chose to drop out of university, rather than continue studying.

The founders of some of the world's biggest companies including Mark Zuckerberg (Facebook), Larry Ellison (Oracle) and Carl Icahn (Icahn Capital Management) all dropped out of university, but now all feature in the Forbes list.

Even Forbes' top billionaire, Bill Gates, who has a current net worth of $78 billion, chose to drop out of the prestigious Harvard University.

With 68 percent having received a degree, Trilby Rajna, Editor at Approved Index and author of the findings, told CNBC that "having a degree does increase your chance of hitting the big time," however, "what connects these billionaires is not what they studied, and that it is possible to achieve anything no matter what your background or passion is."

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