U.S. stocks trade mixed ahead of Yellen's speech

U.S. stocks traded in a narrow range in the morning session on Wednesday, as investors awaited comments from U.S. Federal Reserve Chair Janet Yellen.

At midday, the Dow Jones Industrial Average was down 48.80 points, or 0.27 percent, to 17,839.55. The S&P 500 shed 8.13 points, or 0.39 percent, to 2,094.50. The Nasdaq Composite Index was up 3.73 points, or 0.07 percent, to 5,160.04.

Yellen is scheduled to speak on the U.S. economy later Wednesday at the Economics Club of Washington. Wall Street expected that could add the possibility of an interest rate hike this month.

Atlanta Fed President Dennis Lockhart, a voting member of the policy-setting Federal Open Market Committee (FOMC), said Wednesday the next Fed meeting could be "historic."

On the economic front, U.S. private sector employment increased by 217,000 jobs from October to November, beating market estimates, according to the ADP National Employment Report released Wednesday.

The ADP figure is watched closely as a pre-indicator for the non-farm payrolls report due out Friday.

Traders were also looking to the key November employment data, the last jobs report for the year before the Fed decides on interest rates at its December meeting.

U.S. stocks posted solid gains Tuesday to kick off the last month of the year, as investors awaited key economic data and policy decisions by major central banks later this month. Enditem