shares of united parcel service inc cl b ups slid 168 to 18121 thursday on what proved to be an allaround rough trading session for the stock market with the sp 500 index spx falling 249 to 389575 and dow jones industrial average djia falling 225 to 3320222 the stocks fall snapped a threeday winning streak united parcel service inc cl b closed 5251 below its 52week high 23372 which the company reached on february 1st