U.S. Stocks Open Lower; Set To End Quarter Higher

U.S. stocks opened lower on Tuesday, giving up some of the solid gains booked during the past two sessions. The main indexes were set to end the month lower, but still booked gains over the past quarter. Tuesday's losses were likely driven by concerns over upcoming quarterly results. The S&P 500 opened 9 points, or 0.5%, lower at 2,076. The Dow Jones Industrial Average shed 88 points, or 0.5% to 17,888. The Nasdaq Composite began the session down 21 points, or 0.4%, to 4,927.