How Billionaires Got So Rich In 2021 Marlene Awaad/Bloomberg, Jamel Toppin for Forbes, Michael Prince for Forbes The vast majority of the billionaires on this year’s Forbes list hail from these 10 sectors. There are a record-smashing 2,755 billionaires in the world, according to Forbes’ 2021 World’s Billionaires list. How did they make their mega-fortunes? By doing everything from starting hedge funds and tech companies to breeding pigs and brewing kombucha. But certain industries offer a more common route to riches than others. The most likely way to make a billion-dollar fortune: go into finance and investments. That sector has minted the most billionaires in the world, with 371 people, or about 13% of the entire list. It was the top industry for billionaires in 2020—the last time we tabulated the number of billionaires per industry—as well. The number of finance and investment billionaires has grown by 50% in the past year, and has nearly doubled from two years ago, with household names like Berkshire Hathaway’s Warren Buffett, Carl Icahn and hedge fund titan Ray Dalio. There’s still space for newcomers, however, like the Winklevoss twins, who join the list this year thanks to big bets on cryptocurrency, and Jeff Yass, founder of trading firm Susquehanna International.