In the shadows of giants
This article examines the increasing concentration of US equity market capitalization in a few mega-cap companies, a phenomenon not seen since the mid-1960s. It explores the implications of this concentration for market performance and benchmarking, drawing parallels with historical trends. The author concludes that a broad-based, capitalization-weighted approach remains an efficient way for benchmarks to adapt to evolving market leadership.
https://www.spglobal.com/en/research-insights/special-reports/look-forward/partner-perspectives/unlocking-potential-ahead-with-vanguard/in-the-shadows-of-giants