JPMorgan Chase's head of technical strategy, Jason Hunter, noted that the S&P 500 is approaching long-term resistance, while AI-related stocks continue to weaken, with the Philadelphia Semiconductor Index still down about 22% from its peak. Ned Davis Research's sentiment indicator shows the market has entered an "overly optimistic" zone. BTIG analyst Jonathan Krinsky added that sector rotation has failed to bring new momentum to the broader market. Historical data shows that over the past 30 years, the S&P 500 has fallen by an average of 0.8% in September, making it the worst-performing month of the year.