U.S. stocks fell at the open on Tuesday but quickly moved into positive territory as retail sales advanced at their fastest clip in over three years while producer prices rose more than expected in August.

The Dow Jones industrial average <.DJI> was up 17.16 points, or 0.18 percent, at 9,643.96. The Standard & Poor's 500 Index <.SPX> gained 1.59 points, or 0.15 percent, at 1,050.93. The Nasdaq Composite Index <.IXIC> climbed up 4.90 points, or 0.23 percent, to 2,096.68.

(Reporting by Angela Moon; editing by Jeffrey Benkoe)

Retail sales