Feb. 22 (UPI) -- Billionaire Warren Buffett , marking 60 years leading Berkshire Hathaway, told shareholders in his annual letter released Saturday that he continues to prefer stocks despite a higher cash position. Advertisement Berkshire's latest quarterly results and annual report released Saturday morning showed cash and equivalents at $334.2 billion in the fourth quarter vs. $325.2 billion in the third quarter and $276.9 billion in the second. The company's fourth-quarter operating profit