Equal-Weighted S&P 500 Beats Market-Cap-Weighted Index by Most Since April 2009

The equal-weighted S&P 500 rose 4.9% in October while its market-cap-weighted counterpart fell 0.9%, a split that underscores how large technology holdings shaped the benchmark’s monthly result.

The market-cap-weighted index ended Oct. 30 down for a second consecutive month. The equal-weighted version recorded its biggest monthly gain since April. Its advantage reached 5.8 percentage points, the strongest relative month since April 2009 and the second-largest since 1990.

The S&P 500 technology sector represents 37% of the index’s market capitalization. Eight companies among the index’s 10 largest are linked to technology or artificial intelligence. Investors questioned the sustainability of the AI trade during October.

Oil prices also climbed amid U.S.-Iran tensions. The benchmark closed Friday at 7,580.07.