Week of 9 September 2019: Bitcoin slips 0.76% while Ether gains 4.33% on light volume
When Bitcoin and Ether move in opposite directions in the same week, what does the price data reveal about the split, and what can it not tell us about its cause?
BTC fell from 10,381.24 to 10,302.01 (-0.76%) while ETH rose from 181.18 to 189.03 (+4.33%), a 5.09 point gap. Dollar volume on both was below the prior 12-week average (BTC 0.53x, ETH 0.60x). The ETH/BTC ratio gained 5.14%, and both closed in the upper third of their weekly ranges.
What the data shows. The two assets diverged on direction and on timing. BTC set its high of 10,480 on Monday 9 September at 11:00 UTC and its low of 9,880 on Wednesday 11 September at 06:00 UTC, so its high came before its low. ETH did the reverse: its low of 173.00 came on Wednesday at 16:00 UTC and its high of 190.45 on Sunday 15 September at 00:00 UTC. ETH's best day was Saturday 14 September (+3.96%), while BTC's best was Thursday 12 September (+2.52%) and its worst Tuesday 10 September (-1.98%). Hourly correlation was 0.70, close but not locked together. The ETH/BTC ratio rose 5.14%. Both closed in the upper third of their weekly ranges (BTC at 70.3% of the range and ETH at 91.9%). BTC's week ranked at the 37th percentile and ETH's at the 71st, out of 82 weeks of history; three of the prior four weeks were down for both.
What it does not show. The data records prices and volumes, not who traded or why. A rising ratio can reflect ETH strength, BTC weakness, or both, and these closes cannot separate them. Volume below the prior 12-week average (0.53x for BTC, 0.60x for ETH) says the move was lightly traded, which makes it weaker evidence of a lasting shift. No funding data exists for ETH here, and BTC funding at 0.01% per eight hours was flat all week, offering no signal about crowding.
What a careful desk would check. Realised volatility was 35.2% annualised for BTC and 41.6% for ETH, both modest. The BTC weekly range of 6.07% and ETH's 10.09% were reached on thin volume, so a desk would ask whether the ETH follow-through holds when volume returns to its average, and whether a later week trades back above BTC's high of 10,480.
What would change this reading
- If volume on either asset returns towards its prior 12-week average while the ETH/BTC ratio keeps rising, the split reads as a genuine rotation rather than a thin-market artefact.
- If a later BTC week closes above 10,480, the modest -0.76% week reads as consolidation inside the prior decline.
- If ETH gives back the 5.14% ratio gain while its close was 91.9% up the weekly range, the Sunday high was a spike rather than a base.
- If BTC weekly returns continue to print below the 37th percentile, the recent three-of-four down weeks extend into a longer decline.
Terms
- ETH/BTC ratio
- the price of Ether divided by the price of Bitcoin; it rises when Ether outperforms Bitcoin
- percentile
- the share of past weeks with a lower value; the 37th percentile means 37% of the 82 weeks were lower
- realised volatility
- how much the price actually swung over the period, expressed as a yearly percentage