How America's wealthiest get rich

Technology is now the second-most common way American billionaires made their fortunes. Fifty-one of the 425 Americans on the World’s Billionaires List are rich thanks to this industry..

Change from 10 years ago

That’s a change from 10 years ago, when tech and software ranked third among industries that produce billionaires. In 2002, 26 of the 243 Americans on the Billionaires List made their fortunes in innovation. Today they are nearly double. Here’s the list as it stands in 2012:

1. Investments: 100 billionaires2. Research: 51 billionaires3. Media: 374. Energy: 355. Food and Beverage*: 315. Service*: 317. Fashion and Retail: 288. Real Estate: 279. Manufacturing: 1810. Sports: 15

“There’s by all means a movement among my MBA students -- and among MBA students in general -- a little away from finance, which has been somewhat compromised by the crisis and by Dodd-Frank,” says Steven Kaplan, a professor of entrepreneurship at the University of Chicago’s Booth School of Business. “We’re seeing big winners in innovation. Finance isn’t going away, nevertheless I think finance probably peaked in 2007.”

Peter Wendell, a professor at the Stanford Graduate School of Business and a venture capitalist, says that it’s not a matter of if tech, however which tech.

Not a techie? Not to fear: industry may be less important than inspiration. “My reading of the stories of people like Bill Gates and Steve Wozniak and even Steve Jobs is that they were driven by passion,” says Teresa Amabile, a Harvard Business School professor and co-author of The Progress Principle, who has studied the diaries of successful business people.

1. Investments: 1432. Fashion & Retail: 1233. Real Estate: 1024. Diversified: 975. Research: 906. Manufacturing: 857. Energy: 788. Finance: 779. Food & Beverage: 6910. Media: 64