Bitcoin-S&P 500 Correlation Strengthens Over a Decade as Momentum Slows

Bitcoin (BTC) has grown more closely correlated with the S&P 500 over roughly a decade, and a cumulative gauge moved above zero for the first time since 2015.

The gauge is a cumulative Z-score built from rolling 90-day comparisons of BTC and S&P 500 returns; it reached 98.5. A reading above zero indicates correlation is higher than usual, while a reading below zero indicates it is lower. The cumulative score combines deviations to show the broader trend.

The short-term rate of change in the 90-day correlation eased from a recent high to +6.3%. The positive reading indicates the correlation remains above average but has not been strengthening as quickly.

The slowdown may reflect market maturation, with ETFs and easier trading access potentially changing how financial professionals use Bitcoin. The new threshold adds a marker to Bitcoin’s rising relationship with U.S. stocks.