The S&P 500 was down 0.8% in midday trading to 2,148.28.
The Dow Jones Industrial Average was down 0.8% to 18,113.52.
The NASDAQ was down 0.9% to 5,260.66.
The yield on a 10-year Treasury bond fell 2.2% to 1.58%.
The price of gold rose 0.2% to $1,344.
Aliso Viejo-based Sunstone Hotel Investors Inc. was down 3.4% to $12.60 and a $2.7 billion market cap. Morgan Stanley downgraded the hotel REIT’s shares to “underweight” and cut its price target to $11 from $13.
Newport Beach-based William Lyon Homes was up 3.5% to $18.32 and a $580 million market cap on high volume. The home builder’s shares have risen 17% over the last three trading sessions.