The S&P 500 Index's ability to provide diversification has reached an all-time low, according to a report from Societe Generale. Analysts highlight that the index is highly concentrated, offering no more diversification than a portfolio of fewer than 50 equally weighted stocks. This trend is echoed by various experts who note that cap-weighted indices are increasingly failing to deliver the diversification benefits they once did. As a result, investors are being advised to consider equally weighted index ETFs as an alternative to mitigate the risks associated with market concentration.