shares of canadian national railway co cnr slipped 264 to c15830 friday in what proved to be an allaround negative trading session for the canadian market with the sptsx composite index gsptse falling 077 to 1938772 canadian national railway co closed c1709 below its 52week high c17539 which the company achieved on december 13th trading volume of 28 m shares eclipsed its 50day average volume of 13 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