shares of bristol myers squibb co bmy slumped 056 to 6710 thursday on what proved to be an allaround favorable trading session for the stock market with the sp 500 index spx rising 176 to 396028 and the dow jones industrial average djia rising 117 to 3224655 the stocks fall snapped a threeday winning streak bristol myers squibb co closed 1434 below its 52week high 8144 which the company reached on december 1st the stock underperformed when compared to some of its competitors thursday as johnson