shares of lyondellbasell industries nv cl a lyb slumped 091 to 9581 monday on what proved to be an allaround positive trading session for the stock market with the sp 500 index spx rising 031 to 398224 and the dow jones industrial average djia rising 022 to 3288909 lyondellbasell industries nv cl a closed 2141 below its 52week high 11722 which the company achieved on may 31st