Week of 17 August 2026: Bitcoin gains 23.58% and Ether 31.31%, both at the 99th percentile
After four mixed weeks, what does a week in which Bitcoin gains 23.58% and Ether 31.31% say about the strength of the move, and what can price data alone not establish?
BTC rose from 62,900 to 77,734 (+23.58%) and ETH from 1,876.01 to 2,463.41 (+31.31%), each ranking at the 99th percentile of 444 weeks. Both lows came in the first hour of Monday 17 August. Volume was 1.64 times the prior twelve-week average for BTC and 2.31 times for ETH.
What the data shows. BTC opened at 62,900 and closed at 77,734, a gain of 23.58%. ETH rose from 1,876.01 to 2,463.41, a gain of 31.31%. Both assets set their weekly lows in the first hour of Monday 17 August, 62,751.1 for BTC and 1,872.46 for ETH, so the open sat only 0.24% above the week's low for BTC and 0.19% for ETH. BTC reached 79,500 at 08:00 UTC on Friday 21 August and ETH 2,546.78 at 22:00 UTC the same day. The four weeks before were mixed for BTC (1.05%, -2.8%, 2.09% and -3.08%). Trading activity was well above normal: BTC dollar volume was 12.22bn, 1.64 times its prior twelve-week average, and ETH 7.69bn, 2.31 times. Each return ranked at the 99th percentile of 444 weeks.
What it does not show. The data records prices and volumes only. It does not identify who was buying or what produced the move. It also does not say whether the rise holds. BTC's best day, +7.27% on Friday 21 August, was followed by the worst day of the week, -1.61% on Saturday 22 August. ETH's best day was +17.46% on Wednesday 19 August and its worst -3.72% on Saturday 22 August. At the close BTC remained 38.31% below its 52-week high and ETH 48.29% below its own.
What a careful desk would check. Realised volatility, how much prices actually swung scaled to a yearly figure, reached 58.7% for BTC and 84.4% for ETH. The largest hourly move came in the same hour on Wednesday 19 August, 15:00 UTC: +3.99% for BTC and +5.85% for ETH. Funding stayed positive all week, averaging 0.0076% per eight hours for BTC and 0.0077% for ETH, with a low of 0.0016% and 0.0022%. A positive rate means holders of long positions paid holders of short ones, so a desk would ask whether that carry sits inside its expected return.
Ether against Bitcoin. ETH gained 7.73 percentage points more than BTC and the ETH/BTC ratio rose 6.25%. The two moved together at an hourly correlation of 0.8, so the week reads as one shared advance with Ether in front rather than two separate markets.
What would change this reading
- If BTC trades below this week's low of 62,751.1 in a later week, the advance reads as a sharp rally inside a wider decline rather than a turn.
- If funding stays positive while price stops moving above 79,500, longs keep paying to hold a position that has stopped rising.
- If the ETH/BTC ratio gives back its 6.25% gain, the relative move that marked this week does not hold.
- If a later week of similar size arrives without volume of 1.64 times the prior twelve-week average for BTC, the relationship between activity and return looks different.
Terms
- realised volatility
- how much the price actually swung over a period, expressed as a yearly percentage
- percentile
- the share of past weeks with a lower value; the 99th percentile means 99% of the 444 past weeks were lower
- funding rate
- the periodic payment between long and short holders of a perpetual futures contract; positive means longs pay shorts