Equal-Weight S&P 500 Outperforms Cap-Weighted Index by Widest Margin Since 2009

Equal-weighted S&P 500 stocks posted their largest monthly outperformance over the market-cap-weighted benchmark since 2009 in October 2026. The equal-weight index surged 5.0%, with the Invesco S&P 500 Equal Weight ETF (RSP) advancing 5.0%, while the cap-weighted S&P 500 fell about 0.8% to 0.9%. More than 70% of S&P 500 constituents registered gains, driven by rotation away from mega-cap technology and into energy, consumer staples, utilities, and healthcare. Despite the outperformance, the RSP-to-SPY ratio remained near historical multi-decade lows of approximately 0.29.