Bitcoin’s 3-Sigma Volatility Days Hit 10 in 2026, Topping Full-Year 2018

The striking part is the divergence: extreme days are clustering more often even as baseline volatility and the average size of those spikes both compress. That suggests a market where routine trading is calmer but shocks arrive more frequently — a different risk profile than 2018's, not simply a wilder one. The comparison with Nvidia, the S&P 500 and gold since 2024 frames Bitcoin's tail behaviour as an outlier among major assets. Whether this frequency persists as annualized volatility keeps falling is the open question.