Carlos Slim remains the world's richest person for a second year with estimated assets of $74 billion, according to Forbes magazine's annual ranking of billionaires.
The net worth of Mexico's Slim, 71, whose holdings include the largest mobile phone operator in the Americas, rose $20.5 billion. Bill Gates, 55, chairman of Microsoft Corp., was second again, as his net worth rose $3 billion to $56 billion.
Warren Buffett, 80, chief executive officer of Berkshire Hathaway Inc., held on to third place with $50 billion.
There were a record number of billionaires in 2011, with 1,210 total, compared with the previous high of 1,125 in 2008, and there were 214 newcomers in 2011, with 54 from China and 31 from Russia.
