NEW YORK (MarketWatch) -- U.S. stocks opened slightly higher as investors weighed a barrage of mixed earnings and a much stronger-than-expected jobless claims report. A weekly tally of unemployment benefits fell to the lowest level since 2000, but analysts warned that it may be due to holidays and weather. The S&P 500 opened up 3 points, or 0.1%, at 2,004. The Dow Jones Industrial Average added 49 points, or 0.3%, to 17,236 at the open. The Nasdaq Composite began the day little changed at 4,640.