You should be cautious with stocks in October. This idea has circulated in financial markets for decades. Several of the most memorable market crashes in history occurred in October, from the sharp sell-off during the 1929 Wall Street crash to Black Monday in 1987. Over time, this gave rise to what investors now call the October Effect. Recent Korean market data also suggests that October has not always been an easy month for investors. Over the past 10 years, the KOSPI rose in October four time