U.S. stocks turned negative by mid-afternoon with losses accelerating in the final hour. The late-day selloff wiped out any gains for February. General Electric (GE) committed to aggressive cost cuts this year in an annual letter to shareholders. The company plans to double its restructuring spending to $3.4 billion this year as it streamlines operations to weather slowing global growth. Yahoo! (YHOO) estimates it will book restructuring charges as high as $78 million, the bulk of which it will incur in the first quarter of this year. Valeant Pharmaceuticals (VRX) extended its decline on reports it is under investigation by the Securities and Exchange Commission. The new investigation is separate from an ongoing one into its purchase of Salix Pharmaceuticals last year. TheStreet's Keris Lahiff reports from Wall Street.