Add this tidbit to the proof that the rich are getting richer: Billionaire investor Warren Buffett gained an estimated $12.7 billion in 2013, or a jaw-dropping $37 million a day. That hikes his net worth to $59.1 billion, according to research firm Wealth-X.
Although Buffett gained the most wealth in 2013, it didn't vault him to the top of the list of the world's richest. That honor still belongs to Bill Gates, chairman of Microsoft, who made $11.5 billion in 2013, boosting his net worth to $72.6 billion. He's second on the list of billionaires who increased their wealth the most this year.
Collectively, the top 10 billionaire gainers in 2013 added $101.8 billion to their personal balance sheets. Their combined wealth now totals $347 billion. On average, they earned $29 million per day, increasing their wealth by 41.6 percent for the year. Compare that to the 24 percent increase this year in the S&P 500.
The top five on the list are American. Third, after Buffett and Gates, is casino magnate Sheldon Adelson. He added $11.4 billion to his fortune, which now stands at more than $35 billion.
Amazon's Jeff Bezos, who gained $11.3 billion in 2013, is fourth on the list. His personal fortune is now $34.4 billion. Mark Zuckerberg, founder of Facebook, rounds out the top five, with a gain of $10.5 billion that brings his net worth to $24.7 billion. Not bad for a guy who hasn't seen his 30th birthday yet.
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