shares of union pacific corp unp slid 225 to 20948 wednesday on what proved to be an allaround rough trading session for the stock market with the sp 500 index spx falling 156 to 392886 and dow jones industrial average djia falling 181 to 3329696 union pacific corp closed 6946 below its 52week high 27894 which the company reached on march 31st trading volume 27 m remained 196856 below its 50day average volume of 29 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