Morning Movers: Seadrill Sinks on Stormy Forecast; General Motors Gains on Upgrade

The market look set for a lower open this morning after Chinese stocks tumbled 6.5% today. Bloomberg S&P 500 futures have fallen 0.2%, while Dow Jones Industrial Average futures have dropped 03%. Nasdaq Composite futures have declined 0.2%. Costco Wholesale (COST) has dropped 0.8% to $144.25 after it beat earnings forecasts but missed on revenue. [...]