This Index Just Did Something It Hasn't Done Since 2009. Is It Time To Buy?

The Invesco S&P 500 Equal Weight ETF (RSP) gained 5% in October while the S&P 500 fell 0.8%, its biggest monthly outperformance since 2009. That 5.8-point spread against the cap-weighted benchmark signals a sharp rotation out of mega-cap tech.

Money moved toward defensive sectors: energy, consumer staples, utilities and healthcare. Breadth held up even as the index slipped, with 70% of S&P 500 components finishing the month higher.

The article ties the shift to cooling AI enthusiasm. Because tech concentration drives the cap-weighted index, a pullback in the biggest names can drag the benchmark lower even while most constituents advance. VOO, which tracks the S&P 500, absorbed the 0.8% decline, while RSP's equal weighting spread exposure across all components rather than concentrating it in a handful of names.

Interpretation: the October divergence reads as a market testing whether leadership can broaden beyond a narrow group of tech heavyweights. Names such as NVDA, MSFT, AAPL, GOOGL, META and AVGO carry outsized index weight, so their direction largely determines whether the benchmark keeps lagging its equal-weight counterpart.