shares of western union co wu rallied 147 to 1103 thursday on what proved to be an allaround favorable trading session for the stock market with the sp 500 index spx rising 036 to 410502 and the dow jones industrial average djia rising 001 to 3348529 western union co closed 894 below its 52week high 1997 which the company achieved on april 21st trading volume 67 m remained 36 million below its 50day average volume of 103 m