Bitcoin (BTC) is 66450.4× the size of EthereumPoW (ETHW) by market capitalisation. Their daily returns move closely together (correlation 0.66 across 38 shared trading days). ETHW has been the more volatile of the two, at 86% annualised against BTC's 44%.
ETHWBTC
0.66over 38 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 | ETHW | BTC |
|---|---|---|
| Max drawdown (400d) | -27.0% | -53.0% |
| Risk-adjusted return (90d) | -0.22 | 0.51 |
| Best 30 days (past year) | — | +26.8% |
| Worst 30 days (past year) | — | -32.9% |
Relative strength over 90 days: BTC outperformed ETHW by 16.2% — measured on the ETHW/BTC ratio, so it holds regardless of market direction.