US futures sink ahead of the open, as trade tumult continues to rattle investors By: CNBC.com News June 25, 2018 at 05:47 AM EDT U.S. stock index futures tumbled deep into the red ahead of Monday’s open, following negative trade seen in markets overseas. Read More >> Related Stocks: Carnival Corp Dow Industrials SPDR Nasdaq ETF S&P 500 Ishares Core ETF SPDR S&P 500 ETF Trust