Shares of UnitedHealth took a historic tumble Thursday after the U.S.’ largest health insurer fell far short of Wall Street’s estimates in its quarterly earnings report, dragging down the blue chip Dow Jones Industrial Average with it.

U.S. stocks are mostly higher in the final day of trading for their holiday-shortened week. The S&P 500 was 0.3% higher in early trading Thursday, and a recovery for tech stocks following their sell-off the day before helped push the Nasdaq composite up 0.