Which degree is most likely to make you a billionaire?

Who wants to be a millionaire? Nobody with a chance of becoming a billionaire, that's for sure. But it's a small, select club that ever actually makes it to that seven-figure salary.

Billionaires like Bill Gates, Warren Buffett and Mark Zuckerberg sometimes seem to belong to a different species to the rest of us. But they had to come from somewhere - so what educational and career choices did they make, and could you try and follow in their footsteps?

A new report by business-to-business commerce platform Approved Index examines the background of the world's richest 100 people. And, it turns out, the first thing you should do is be born in the US.

Forty percent of the world's billionaires come from North America - all but one of these from the US - compared with 29% from Europe and 22% from Asia. Africa and Australia have only produced one billionaire each so far.

When it comes to education, perhaps surprisingly it turns out that nearly a third of the richest 100 billionaires, 32%, have no university degree at all.

However 22% studied engineering and 12% business, making these far and away the best degrees for making serious money. The arts between them accounted for only 9% of the top 100, just ahead of economics, with 8%. Finance, science, maths and the law accounted for two or three percent of billionaires each.

It's engineering that makes for the richest billionaires too, with an average wealth of $25.77 billion each; those with no degree average $24.03 billion and those with a business degree $22.5 billion.

But if you're thinking that no degree means no education, think again. Bill Gates, the richest man in the world, was a Harvard law student before dropping out to co-found Microsoft - and has commented: "If young people understood how doing well in school makes the rest of their life so much interesting, they would be more motivated."

Mark Zuckerberg, too, was reading computer science at the same university before quitting to focus on Facebook and become the youngest of the world's 100 richest billionaires, with an estimated $33.4bn net worth.

"All of my friends who have younger siblings who are going to college or high school - my number one piece of advice is: you should learn how to program," he says.

And, he adds, "When I was in college I did a lot of stupid things and I don't want to make an excuse for that."

The Approved Index report doesn't examine which universities produce the most billionaires. But according to the 2014 Billionaire Census, published by Wealth X and UBS, that's pretty US-centric too. The University of Pennsylvania heads the list, with 25 billionaire graduates altogether; Harvard is second, with 22, and Yale third with 20.

And once they finish their education, where should wannabe billionaires exert their talents? Well, there's no prizes for guessing that it's the field of technology. According to Approved Index, 19% of the top 100 billionaires made their money this way. Retail is the second-best career path for billionairedom, as demonstrated by Walmart's Walton family, for example.

Real estate came third, with 7.1%, and non-profit and soxial organisations are the main source of wealth for 5%. Textiles, clothing and luxury goods bring in the cash for 5%.

And, after all that, what does the average billionaire look like? Well, according to the research, he's almost certainly a man. His average age is 67.5, there's a seven-in-ten chance he's married, and he has an average of three children.

If you're thinking there's no chance of you, or anyone in your family, becoming a billionaire, think again. According to the Billionaire Census, the majority are self-made. Only one in five have inherited all their wealth - and they tend to be less rich than those that made it for themselves. Maybe it's time to sign up for that engineering degree.

Degrees held by the world's richest people
1. None (32)
2. Engineering (22)
3. Business (12)
4. Arts (9)
5. Economics (8)
6. Finance (3)
7. Science (2)
8. Mathematics (2)
9. Law (2)
10. Other (8)

Average wealth by degree
Engineering $25.77 billion
None $24.03 billion
Business $22.5 billion
Economics $22.1 billion
Arts $20.51 billion
Other $19.66 billion
Mathematics $17.75 billion
Finance $15.83 billion
Law $13.2 billion
Science $12.05 billion

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