S&P 500 Index Futures Lower In Volatile Trading By: Benzinga via Benzinga May 12, 2015 at 10:28 AM EDT Joel Elconin is the co-host of Benzinga's #PreMarket Prep, a daily trading idea radio show. S&P 500 index futures are trading ... Read More >> Related Stocks: Exxon Mobil SPDR S&P 500 ETF Trust