NEW YORK (Reuters) - Warren Buffett's Berkshire Hathaway Inc said fourth-quarter profit surged, helped by derivatives bets tied to global stock markets, though operating profit fell 40 percent as the weakened economy weighed on several businesses.

Profit rose for a third straight quarter, and full-year profit increased 61 percent, as Berkshire rebounded from perhaps its worst year since Buffett took over in 1965.

"I was quite impressed with the results," said Vahan Janjigian, author of the book "Even Buffett Isn't Perfect." More Information .......

http://www.reuters.com/article/idUSTRE61Q1IF20100227