The S&P 500 was flat at 3,916.02 during midday trading.
The Dow Jones Industrial Average rose 0.1% to 31,410.18.
The Nasdaq climbed 0.3% to 14,024.56.
The yield on a 10-year Treasury bond fell 0.9% to 1.15%.
The price of gold increased 0.3% to $1,839.30.
The price for a barrel of oil was up 0.6% at $58.30.
Clean Energy Fuels Corp. (Nasdaq: CLNE) in Newport Beach rose 4.8% to $18.73 apiece for a market cap of $3.7 billion, continuing a surge that started yesterday when the company announced a multi-year contract with LA Metro.
Costa Mesa-based restaurant operator El Pollo Loco Holdings Inc. (Nasdaq: LOCO) rose 5.4% to $20.66 apiece for a market cap of $753 million. The company said last week it plans to expand its franchises in the western U.S. and parts of Texas.