Stocks were nearly flat after the start of trading on Wednesday as a warning for Spain about its credit rating fanned worries about the debt crisis in the euro zone, while U.S. economic data showed further improvement in the recovery.

The Dow Jones industrial average <.DJI> was down 4.23 points, or 0.04 percent, at 11,472.31. The Standard & Poor's 500 Index <.SPX> was down 2.31 points, or 0.19 percent, at 1,239.28. The Nasdaq Composite Index <.IXIC> was down 2.76 points, or 0.11 percent, at 2,624.96.

(Reporting by Caroline Valetkevitch)