S&P 500 stock-index correlation hits record low of +0.10

The median 63-day correlation between individual S&P 500 stocks and the index has dropped to +0.10, the lowest on record. That is down 71% over five months and below the prior low of +0.16 after the 2000 dot-com bubble. The reading suggests extreme concentration in a handful of names driving the index while most stocks move independently.