News Summary: Forbes lists world's billionaires
TOP BILLIONAIRES: Forbes magazine said Monday that Mexico's Carlos Slim is still the richest person in the world, topping its annual tally of billionaires for the fourth straight year. Microsoft Corp.'s Bill Gates held on to the No. 2 spot.
BUFFETT BOUNCE: Warren Buffett of Berkshire Hathaway Inc. fell out of the top three for the first time since 2000. He landed in the fourth position, behind Spanish clothier Armancio Ortega.
ZUCKERBERG SLIPS: Facebook Inc.'s Mark Zuckerberg saw his ranking drop 31 spots to No. 66 as his net worth declined by $4.2 billion.