For the first time in a decade, Warren Buffett is not one of the two richest billionaires in the world, as ranked by Forbes magazine.
Forbes says Berkshire Hathaway's stock gains over the past year contributed to a $10 billion increase in Buffett's personal wealth, to $47 billion from last year's $37 billion.
But Slim's fortune increased by $18.5 billion to $53.5 billion as prices soared for his telecom holdings, putting him into the top spot. Forbes notes that shares of America Movil gained 35 percent in a year. Slim owns a stake worth $23 billion.
It is the first time since 1994 that the world's richest billionaire has not been from the United States.
Even a $13 billion increase for Bill Gates, from $40 billion to $53 billion, wasn't enough to keep him in the top slot. It's only the second time in five years that Gates hasn't been number one.
Buffett, however, lost his title of world's richest billionaire just six months later when he came in number two behind Gates in the magazine's list of the 400 richest Americans.