Daily research · Big market days · written
What does Ether do the day after Bitcoin rises 3% or more?
Short answer
Across 458 cases since 2017, the typical move for Ether the day after Bitcoin rises 3% or more was −0.65%. Lower was the outcome 55% of the time. The best tenth gained +5.4% or better and the worst tenth −4.8% or worse. Out of sample, calls like it showed no clear edge.
Typical move
−0.65%
the next day, the middle case
How often
55%
it ended lower
Best 1 in 10
+5.4%
or better
Worst 1 in 10
−4.8%
or worse
Cases
458
2017-2026, on 458 days
Higher 44% of the time against 52% on ordinary days (431 days compared): higher less often than on ordinary days.
Share on Xcopy link§ 01 · The pattern458 cases
The pattern, exactly
as of · the rule, the data, the dates
A case is a day Bitcoin closed 3% or more above the day before (UTC daily closes), and the move that counts is Ether's.
Each of the 458 moves is measured from the close of the day it happened to the close 1 day later.
In our data that gives 458 measured cases on 458 separate days, from Aug 24, 2017 to Sep 21, 2026; the numbers were written on Oct 7, 2026.
§ 02 · Why it might work
Why it might work
as of · the idea traders have in mind, not a promise
Bitcoin is the market's anchor. A big up day pulls money and attention back into crypto, and one reason traders watch the days after is the idea that the move spreads to the rest of the market. Others expect part of a sharp jump to be given back once the latecomers are in.
That is the reasoning behind watching Bitcoin's 3% jumps; whether it held over our 458 cases since 2017 is what the next sections measure.
§ 03 · How we tested it
How we tested it
as of · our own closes, against ordinary days
- Every one of the 458 cases is measured from the close of the day it happened to the close 1 day later, on our own daily closes (UTC).
- Each case is set against Ether's own ordinary days (1-day moves starting in the 365 days before it, at least 90 of them), and 431 of the 458 days had that many to compare.
- No two cases share a day, so each of the 458 days counts once.
- Out of sample: each calendar quarter, the lab re-ran its coin-by-coin search on the data before that quarter only, then scored every call the proven drivers of this kind made in the quarter after, against how often the same side won on any day of the same coin's quarter.
§ 04 · Results155 up · 198 down
Results
as of · every past case, Aug 24, 2017 to Sep 21, 2026
Of the 458 cases, 155 ended up, 198 down and 105 sideways (within ±1.1%) a day later; the middle case −0.65%, the average day −0.19%.
ended up (155)ended down (198)sideways, within ±1.1% (105)each line one real case · past cases, not a projection
1, 7 and 30 days against ordinary days
| After | Cases | Typical move | Typical, ordinary days | Higher | Higher, ordinary days | Against ordinary days |
|---|---|---|---|---|---|---|
| 1 day this post | 458 | −0.65% | +0.04% | 44% | 52% | higher less often than on ordinary days |
| 7 days | 240 | −0.36% | +0.38% | 48% | 53% | no clear edge over ordinary days |
| 30 days | 88 | +3.6% | +0.94% | 52% | 52% | no clear edge over ordinary days |
At the other horizons: 7 days, typical −0.36% over 240 cases; 30 days, typical +3.6% over 88 cases.
By year, the typical move ranged from −1.7% in 2018 to +0.58% in 2021; 7 of 10 years leaned the same way as the whole.
Year by year
| Year | Cases | Typical move | Higher | Lower |
|---|---|---|---|---|
| 2017 | 42 | +0.06% | 55% | 45% |
| 2018 | 64 | −1.7% | 38% | 62% |
| 2019 | 45 | −1.4% | 24% | 76% |
| 2020 | 64 | −0.22% | 48% | 52% |
| 2021 | 76 | +0.58% | 55% | 45% |
| 2022 | 40 | −0.89% | 38% | 62% |
| 2023 | 34 | −1.00% | 35% | 65% |
| 2024 | 49 | +0.07% | 53% | 47% |
| 2025 | 25 | −0.37% | 44% | 56% |
| 2026 | 19 | −0.00% | 47% | 53% |
The latest 10 cases
| Day | What happened | 1 day | 7 days | 30 days |
|---|---|---|---|---|
| Bitcoin +6.7% that day | −0.81% | −3.2% | open | |
| Bitcoin +5.8% that day | +0.79% | +3.0% | open | |
| Bitcoin +5.1% that day | −2.1% | −2.8% | +7.2% | |
| Bitcoin +7.3% that day | −3.7% | −2.9% | +5.1% | |
| Bitcoin +5.3% that day | +8.1% | +7.9% | +13.1% | |
| Bitcoin +7.1% that day | +3.3% | +11.3% | +16.0% | |
| Bitcoin +4.3% that day | +1.4% | +2.0% | −0.30% | |
| Bitcoin +3.4% that day | −0.42% | +2.2% | +6.8% | |
| Bitcoin +4.0% that day | −0.00% | +2.1% | +4.8% | |
| Bitcoin +5.2% that day | −2.0% | −2.3% | −4.7% |
Source: our daily closes and our dated events, measured on .
§ 05 · Out of sampleno clear edge out of sample
Out of sample
as of · calls like it, scored on data they never saw
Out of sample, calls made from Bitcoin's 3% jumps showed no clear edge: right 59% of 98 calls since 2020, against 50% for that side on any day (Oct 21, 2020 – Sep 21, 2026).
The bar to earn a side: right more often than that side won on any day, on 100+ scored calls over 60+ separate days, with an average move its way above 0%; the share above is that record's, not the in-sample rate of the 458 cases here.
§ 06 · Verdict
Verdict
as of · plain, with the caveats
In our data Ether ended higher less often than on ordinary days (44% against 52% over 431 days), and both halves of the history lean the same way.
The typical move of −0.65% is small next to the spread between the best and worst 1 in 10 (−4.8% to +5.4%): single cases went either way by far more.
Out of sample, calls like it showed no clear edge (right 59% of 98 calls since 2020, against 50% for that side on any day).
Markets change, so what Bitcoin's 3% jumps did from 2017 to 2026 can stop working.
§ 07 · Questions
Questions
as of · answered from the numbers above
- Did Ether usually end lower the day after Bitcoin rises 3% or more?
- In 55% of 458 cases from Aug 24, 2017 to Sep 21, 2026.
- Measured the scoreboard's way, day by day, the share higher was 44% against 52% on Ether's own ordinary days.
- What was the typical move?
- The middle case moved −0.65% the next day.
- The best 1 in 10 reached +5.4% or more and the worst 1 in 10 −4.8% or less.
- Is this an edge?
- Not on its own: over 458 cases it shows higher less often than on ordinary days, and out of sample, calls like it showed no clear edge (right 59% of 98 calls since 2020, against 50% for that side on any day).
- The −0.65% typical move is the past's, and a past pattern can stop working.
- When did it last happen?
- The latest was on Sep 21, 2026: Bitcoin +6.7% that day.
- A day later the move was −0.81%.
- Does it depend on the year?
- No. The typical move was +0.58% in 2021 (76 cases) and −1.7% in 2018 (64 cases).