The S&P 500 fell 0.38% to 1,644.24 in afternoon trading Friday.
The Dow Jones industrial average was down 0.23% to 15,259.87, while the Nasdaq was down 0.31% to 3,448.64.
The yield on a 10-year Treasury bond fell 0.59% to 2.01%.
The price of gold was down 0.38% to $1,386.50 per ounce.
Irvine healthcare software maker Quality Systems Inc.'s shares were off about 4% to $17.81, a day after the company reported a loss for the March quarter. Quality had a recent market value of $1.06 billion.
Santa Ana for-profit school operator Corinthian Colleges Inc. was up about 11% to $2.85, leading a general uptick within the education sector. Corinthian had a recent market value of $245.53 million.