A number of billionaires had a very very good year last year. Jeff Bezos saw his net worth rise at the rate of $3.2 million an hour. Bill Gates is the richest person in the world with his $90 billion net worth – $11 billion of which he earned over the past year – but for a few hours in July, Bezos actually topped Gates to become the world's richest person. Currently Gates is only $1 billion richer than Bezos.
Three billionaires added more than $11 billion to their fortunes. Amazon founder Jeff Bezos racked up an additional $22.9 billion on the strength of Amazon's epic year—that's a rate of $3.2 million PER HOUR. Let's take a look at the top 15 world's highest-gainers.
Amancio Ortega: $4.3 billion gain
Net Worth:$80 billion
Zara founder Amancio Ortega has had a very good year. His firm Inditex had a 10% rise in profits as well as a rise in dividend payouts. Ortega owns 60% of Inditex, so that upped his net worth by $4.3 billion.
Carlos Slim: $4.5 billion gain
Net Worth:$52 billion
The richest man in Mexico has had a few bad years. He lost $27.1 billion in 2015. He made $4.5 billion up in 2016, but his overall net worth is still down more than $20 billion from 2015 due to the shares of America Movil bottoming out in 2015. They've been on a recovery since last October.
Sheldon Adelson: $5.2 billion gain
Net Worth: $35 billion
Sheldon Adelson has had an amazing year. The casino mogul is chairman and CEO of Las Vegas Sands, one of the biggest casino companies in the world. The company's stock has been trending up since January 2016, adding $5.2 billion to his net worth.
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Sergey Brin: $5.4 billion gain
Net Worth: $38 billion
Sergey Brin co-founded Google with Larry Page in 1998, after meeting at Stanford a few years earlier. Today, Brin oversees Google's parent company, Alphabet, as its president. Alphabet's soaring stock value boosted his net worth $5.4 billion over the past year.
Larry Page: $5.5 billion gain
Net Worth: $40 billion
Larry Page is the slightly wealthier Google co-founder because he owns more shares in Alphabet than Brin. These days, Page is CEO of Google's parent company, Alphabet. It was Page who came up with the algorithm at the heart of Google's search engine, which compiles results in a specific ranking. Page also led Google's acquisition of Android.
Steve Ballmer: $6.5 billionÂ
Net worth: $28 billion
Microsoft's former CEO boosted his net worth by $6.5 billion over the past year. Ballmer's many holdings, including a 4% stake in Twitter and 100%Â ownership of the Los Angeles Clippers , have performed excellently over the past year.
Michael Bloomberg: $7.5 billion gain
Net Worth: $36. 5 billion
Media mogul Michael Bloomberg added $7.5 billion to his net worth. The Bloomberg Media founder and  ex-mayor of New York City  owns 88% of his  company, which has been posting amazing profits over the last several months.
Bernard Arnault: $7.5 billion gain
Net Worth: $37 billion
Bernard Arnault received his bachelor's degree in engineering and went into the family business, civil engineering firm Ferret-Savinel. In 1984, Arnault acquired the financial firm Financiere Agache-Willot, which controlled the textile company Marcel Boussac. Once he had control of Boussac he went after several subsidiaries, including Christian Dior and high-end French department store Le Bon Marche. Arnault has been the Chairman and CEO of LVMH and Chairman of Christian Dior since 1989. LVMH controls roughly 70 luxury brands including Louis Vuitton, Fendi, and Moet & Chandon. Arnault owns a 62.5% controlling stake in the luxury goods conglomerate.
Jack Ma: $7.8 billion gain
Net Worth: $28 billion
In 1999, Jack Ma brought 18 friends and family members together in his apartment and spent two hours pitching them his vision. Every single person bought in, giving Ma $60,000 to start Alibaba. In 2014, Alibaba.com became the largest Initial Public Offering of all time. China's answer to Amazon isn't slowing down.
Larry Ellison: $8.6 billion gain
Net Worth: $40 billion
Oracle co-founder Larry Ellison has had an amazing year financially. In November, Oracle acquired NetSuite for $9.3 billion. Ellison owned 35% of NetSuite at the time of purchase, so he made $3.5 billion on the deal. This, coupled with Oracle's great year boosted his net worth by $8.6 billion.
David and Charles Koch: $8.7 billion each gain
Net Worth David: $40 billion
Net Worth Charles: $47 billion
David and Charles Koch own 84% of the conglomerate Koch Industries. The company is in manufacturing, commodities trading, ranching, and petroleum refining. Charles Koch is chairman of the board and CEO. David Koch serves as executive vice president.
Bill Gates: $11 billion gain
Net Worth: $90 billion
Bill Gates is the richest man on the planet. He added $11 billion to his net worth over the last year thanks in part to his stock portfolio and its 69 million shares in Berkshire Hathaway. Gates has been a billionaire since Microsoft went public when he was 30. He is also one of the architects of The Giving Pledge. These days, he is a member of Microsoft's board and focuses his time on his philanthropic work
Warren Buffett: $14.8 billion gain
Net Worth: $75 billion
The legendary investor can seemingly do no wrong, and Warren Buffett's Berkshire Hathaway firm is one of the most successful businesses in the world. Since 2009, shares in Berkshire Hathaway have consistently been on the rise. If you had invested $10,000 with Buffett in 1966, you would have $300 million today. He is famously frugal and known for his fondness for junk food and Coca-Cola.
Mark Zuckerberg: $20.1 billion gain
Net Worth: $62 billion
Mark Zuckerberg holds a 24% stake in the social network he co-created. Facebook's share price has skyrocketed in recent months. He first became a billionaire at the age of 23 when Facebook went public. He and his wife Priscilla are members of the Giving Pledge and have pledge to give away 99% of their fortune in their lifetime.
Jeff Bezos: $22.6 billion gain
Net Worth: $89 billion
Jeff Bezos owns 16.9% of Amazon. The stock has been on the rise, and Bezos has seen his net worth skyrocket by $22.6 billion in the past year, equivalent to more than $3.2 million an hour. Jeff Bezos wrote the business plan for what would become Amazon during a cross country road trip with his wife. He single-handedly revolutionized the way we buy books – and after a while, also everything else under the sun.
