shares of thomson reuters corp tri dropped 127 to c15572 thursday in what proved to be an allaround poor trading session for the canadian market with the sptsx composite index gsptse falling 146 to 1960063 thomson reuters corp closed c410 short of its 52week high c15982 which the company achieved on december 13th trading volume of 353221 shares remained below its 50day average volume of 416902