九十月📉不足为奇 Of the 26 occasions in the past 100 years, on which there were drops of 10% or more in a month, 12 happened in either September or October. Those monthly drops were followed by subsequent 12-month gains on 16 occasions, of an average 6.8%. And last month’s 4.8% decline wasn’t particularly unusual -- there have been 89 drops of more than 5% in the past century, though they’ve become far less frequent in recent decades.