Week of 25 August 2025: Ether falls 8.12% while Bitcoin loses 4.62%
When Bitcoin falls 4.62% and Ether 8.12% in the same week with both closing near their lows, what does the difference between the two assets say about which move was the heavier one?
BTC fell from 113,493.59 to 108,246.35 (-4.62%) and ETH from 4,780.15 to 4,391.83 (-8.12%), a gap of 3.5 percentage points. Both set their highs early on Monday 25 August and their lows early on Saturday 30 August. Volume was 1.03 times the prior twelve-week average for BTC and 1.34 times for ETH.
What the data shows. Both assets fell, and Ether fell further. BTC closed at 108,246.35 against an open of 113,493.59, a fall of 4.62%; ETH closed at 4,391.83 against 4,780.15, a fall of 8.12%. Both highs came early on Monday 25 August, BTC at 03:00 UTC and ETH at 00:00 UTC, and both lows came early on Saturday 30 August, so the week ran lower rather than breaking in one session. Both closed in the lower third of their weekly ranges: BTC at 14.2% of the way up its range, ETH at 24.9%. Dollar volume was 12.25 billion for BTC, 1.03 times its prior twelve-week average, and 19.52 billion for ETH, 1.34 times its average.
What it does not show. These candles record prices, not reasons. Nothing here identifies who was selling or whether the selling was forced. The data also cannot say whether the Saturday lows were final. BTC sat 12.6% below its 52-week high and ETH 11.01% below its own, so the week's fall sits inside a longer decline that this week alone cannot describe.
What a careful desk would check. Realised volatility, the size of the swings that actually happened expressed as a yearly figure, reached 33.7% for BTC and 67.8% for ETH, against weekly ranges of 5.88% and 12.7%. The largest hourly move for each came in the same hour, 19:00 UTC on Monday 25 August: -1.5% for BTC and -3.37% for ETH. Funding, the regular payment between long and short holders of perpetual futures, stayed slightly positive on average, 0.0061% per eight hours for BTC and 0.0022% for ETH, with lows of -0.0012% and -0.0014%. A desk would ask whether position sizes assumed one volatility reading or the other.
Ether against Bitcoin. The two moved closely but not identically: hourly correlation was 0.83, and the ETH/BTC ratio, Ether priced in Bitcoin, fell 3.67%. ETH volume ran 1.34 times its prior twelve-week average while BTC ran 1.03 times, so the larger weekly move arrived with heavier activity. Both returns sit near the bottom of their histories, at the 19th percentile for BTC and the 18th for ETH among 393 weeks.
What would change this reading
- If a later week closes below this week's low of 107,350.1 for BTC, the drift lower reads as a new leg down rather than a pause.
- If the ETH/BTC ratio falls by more than 3.67% again in a later week, Ether's underperformance reads as a trend rather than a single week's gap.
- If funding turns negative and stays there while prices keep falling, holders of short positions are paying long ones, which changes the cost of holding a downside view.
Terms
- realised volatility
- how much the price actually swung over a period, expressed as a yearly percentage
- ETH/BTC ratio
- the price of Ether expressed in Bitcoin, showing which of the two moved more
- funding
- the regular payment between long and short holders of a perpetual futures contract that keeps its price close to the spot price