The S&P 500 has achieved its best year-to-date performance through September since 1997, rising 20.8%. This marks a significant milestone, as the index has posted gains in eight of the first nine months of 2024. In September alone, the S&P 500 increased by 1.7%, making it the first winning September since 2019. Additionally, the S&P 500 is up 38% since last October and 35.5% year-over-year, marking the best performance since October 2021. The index has also risen in 10 of the last 11 months. In the third quarter, the S&P 500 gained 5.1%, contributing to its best start to a year since 1997. Historically, when the S&P 500 has performed this well through September, the fourth quarter has also tended to be positive, with a median return of 4.1%. Analysts note that while October has often seen declines following such strong performances, the overall trend for the fourth quarter remains optimistic.