China has the youngest billionaires
China may not have the most billionaires, but it does have the youngest.
According to a report from Wealth-X and UBS, China's 157 billionaires have an average age of 53 years old. That's nine years younger than the global average.
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China has the second-highest number of billionaires in the world after the U.S., which has 515. And China has added 10 new billionaires over the past year.
Still, China's billionaires have come under fire recently for their wealth and power. The government recently charged one of its top billionaires, venture capitalist and human rights supporter Wang Gongquan, with "assembling a crowd to disrupt order."
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Chinese-American entrepreneur and blogger Charles Xue was arrested in August, and last year Xu Ming, once the country's eighth richest man, was arrested and charged with fraud.
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One study found that 17 percent of the billionaires on the Hurun Rich List—China's version of the Forbes list—wind up in court or prison.
—By CNBC's Robert Frank. Follow him on Twitter @robtfrank.