The S&P 500 fell 0.3% in midday trading to 2,649.46.
The Dow Jones Industrial Average fell 0.5% to 24,491.70.
The Nasdaq declined 0.2% to 6,971.74.
The yield on a 10-year Treasury bond dropped 0.4% to 2.85%.
The price of gold increased 0.2% to $1,329.
ChromaDex Corp. (Nasdaq: CDXC) climbed 6.6% to $5.14 and a $276 million market cap. The Irvine nutraceutical company yesterday reported preliminary fourth-quarter revenue jumped 69% to $7.5 million.
Boot Barn Holdings Inc. (NYSE: BOOT) climbed 3.4% to $18.51 and a $502 million market cap. Shares in the Irvine-based western wear retailer have tripled since a 52-week low last June.