11.3 The Lognormal property >It follows from this assumption that lnS-lnS≈d|!y √T or In so √T Since the logarithm of Sr is normal, ST is lognormally distributed Options, Futures, and Other Derivatives, 4th edition@ 2000 by John C. Hull Tang Yincai, C 2003, Shanghai Normal University11.3 Options, Futures, and Other Derivatives, 4th edition © 2000 by John C. Hull Tang Yincai, © 2003, Shanghai Normal University The Lognormal Property ➢It follows from this assumption that ➢Since the logarithm of ST is normal, ST is lognormally distributed 2 0 2 0 ln ln , 2 or ln ln , 2 T T S S T T S S T T   m    m       + −             −  −        