shares of wr berkley corp wrb shed 043 to 5763 tuesday on what proved to be an allaround grim trading session for the stock market with the sp 500 index spx falling 158 to 407163 and dow jones industrial average djia falling 102 to 3353083 wr berkley corp closed 1936 below its 52week high 7699 which the company achieved on december 1st