Warren Buffett's Berkshire Hathaway on Saturday posted its second straight record annual operating profit, with its insurance business benefiting from improved underwriting and higher income from investments as interest rates rose. Net income also reached a record $96.2 billion, as the rising stock market boosted the value of Berkshire's $354 billion equity portfolio, half of which is in Apple. In his annual letter to Berkshire shareholders, Buffett said Berkshire's insurance businesses performed "exceptionally well" -- among them, Geico, where better underwriting qu...