shares of merck  co inc mrk shed 114 to 7554 tuesday on what proved to be an allaround positive trading session for the stock market with the sp 500 index spx rising 178 to 464923 and the dow jones industrial average djia rising 160 to 3549270 merck  co inc closed 1586 short of its 52week high 9140 which the company reached on november 4th the stock demonstrated a mixed performance when compared to some of its competitors tuesday as johnson  johnson jnj fell 032 to 16721 roche holding ag part cert rhhvf fell 051 to 40676 and pfizer inc pfe fell 339 to 5895 trading volume 149 m eclipsed its 50day average volume of 145 m editors note this story was autogenerated by automated insights an automation technology provider using data from dow jones and factset see our market data terms of use