Trade jitters continued to pressure stocks on Thursday, with the Dow Jones Industrial Average (DJINDICES: ^DJI) falling for the eighth straight day. The S&P 500 (SNPINDEX: ^GSPC) lost more than half a percentage point, but is still up for the year.Data source: Yahoo! Finance.Energy stocks were slammed, with the SPDR S&P Oil & Gas Exploration & Production ETF (NYSEMKT: XOP) tumbling 2.6%.