Wall Street opens flat on mixed earnings reports

U.S. stocks opened flat on Wednesday as earnings season began mixed, with Alcoa Inc warning on slowing aluminum consumption but Yum Brands raising its outlook.

The Dow Jones industrial average was down 19.35 points, or 0.14 percent, at 13,454.18. The Standard & Poor's 500 Index was down 0.52 point, or 0.04 percent, at 1,440.96. The Nasdaq Composite Index was down 1.06 points, or 0.03 percent, at 3,063.96.

(Reporting by Ryan Vlastelica; Editing by Kenneth Barry)