Mexican telecom tycoon Carlos Slim is the new richest man in the world, according to Forbe’s annual list. Slim’s wealth increased to $ 53.5 billion in 2009, up by an amazing $ 18.5 billion from a year ago. The meteoric rise of Slim’s fortune is attributed to the increasing value of his telecom companies, which include mobile services provider America Movil.

The increased value of America Movil shares, whose market price surged by 35 percent from 2008, allowed Slim to knock Bill Gates from the top for only the second time in the last 16 years. Gates’ estimated value rose by $ 13 billion on the back of a 50 percent increase in Microsoft’s share price, but fell short of maintaining his hold on the top spot with $ 53 billion.

Taking Slim’s place in third spot is 2008′s richest billionaire Warren Buffet, whose total fortune grew by $ 10 billion over the last 12 months. Buffet is now worth $ 47 billion thanks largely to the performance of his shares in Berkshire Hathaway.

Overall, the total number of billionaires in the world went up to 1,011 from 793 a year ago.