Bitcoin (BTC) is 284.6× the size of Bitcoin Cash (BCH) by market capitalisation. Over the past 1 year, BTC is ahead by 18.4 percentage points (BTC -27.3% against BCH -45.7%). Their daily returns move closely together (correlation 0.63 across 399 shared trading days). BCH has been the more volatile of the two, at 78% annualised against BTC's 44%.
BTCBCH
0.63over 399 shared trading days
Measured on daily returns rather than on prices. Two assets that both simply trend upward score near 1.0 on raw prices whether or not they move together, so returns are what answer the question people mean by correlation.
| Metric | BTC | BCH |
|---|---|---|
| Max drawdown (400d) | -53.0% | -70.9% |
| Risk-adjusted return (90d) | 0.51 | 0.27 |
| Best 30 days (past year) | +26.8% | +34.0% |
| Worst 30 days (past year) | -32.9% | -56.8% |
Relative strength over 90 days: BCH outperformed BTC by 6.4% — measured on the BTC/BCH ratio, so it holds regardless of market direction.