The "September Effect" Is in Full Swing, With Stocks Slumping Left and Right. Here's How History Says Investors Should Respond.

Key Points The September effect refers to September being by far the worst month for stock market performance, on average. The September effect occurs about 55% of the time. October, and especially November, tend to see much stronger gains that investors shouldn't miss. 10 stocks we like better than S&P 500 Index › Beware the September effect! Of all the calendar-related stock market phenomena -- like the Santa Claus rally in December or its follow-up January effect of small-cap stock pops -- none is as feared as this dreaded annual scourge. Missed AI’s "Act 1"? Act 2 Could Be 15x Bigger. Most investors think they missed the AI boat because they didn't buy Nvidia in 2005. But according to our analysts, we’re only at the end of "Act 1"—the R&D phase.