shares of laboratory corp of america holdings lh shed 235 to 23436 thursday on what proved to be an allaround dismal trading session for the stock market with the sp 500 index spx falling 088 to 378538 and dow jones industrial average djia falling 082 to 3077543 laboratory corp of america holdings closed 8281 short of its 52week high 31717 which the company achieved on december 31st the stock demonstrated a mixed performance when compared to some of its competitors thursday as idexx laboratories inc idxx fell 209 to 35073 quest diagnostics inc dgx fell 336 to 13298 and qiagen nv qgen rose 111 to 4720 trading volume 867098 remained 51499 below its 50day average volume of 918597 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