Daily research · Big market days · written
What does Bitcoin do the day after the altcoins rise 4% or more?
Short answer
Across 493 cases since 2017, the typical move for Bitcoin the day after the altcoins rise 4% or more was −0.22%. Lower was the outcome 54% of the time. The best tenth gained +4.1% or better and the worst tenth −4.1% or worse. Out of sample, calls like it showed no clear edge.
Typical move
−0.22%
the next day, the middle case
How often
54%
it ended lower
Best 1 in 10
+4.1%
or better
Worst 1 in 10
−4.1%
or worse
Cases
493
2017-2026, on 493 days
Higher 46% of the time against 53% on ordinary days (490 days compared): higher less often than on ordinary days.
Share on Xcopy link§ 01 · The pattern493 cases
The pattern, exactly
as of · the rule, the data, the dates
A case is a day the 100 most traded altcoins rose 4% or more on average, and the move that counts is Bitcoin's.
Each of the 493 moves is measured from the close of the day it happened to the close 1 day later.
In our data that gives 493 measured cases on 493 separate days, from Nov 7, 2017 to Sep 24, 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
When the biggest altcoins all rise together, it is a broad move rather than one coin's news. Some traders read it as the start of an altcoin run; others expect such broad jumps to cool off once short positions have been closed.
That is the reasoning behind watching 4% altcoin rallies; whether it held over our 493 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
- We measured each of the 493 cases 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 Bitcoin's own ordinary days (1-day moves starting in the 365 days before it, at least 90 of them), and 490 of the 493 days had that many to compare.
- No two cases share a day, so each of the 493 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 · Results149 up · 177 down
Results
as of · every past case, Nov 7, 2017 to Sep 24, 2026
Of the 493 cases, 149 ended up, 177 down and 167 sideways (within ±1.0%) a day later; the middle case −0.22%, the average day −0.10%.
ended up (149)ended down (177)sideways, within ±1.0% (167)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 | 493 | −0.22% | +0.15% | 46% | 53% | higher less often than on ordinary days |
| 7 days | 244 | +0.36% | +0.69% | 52% | 55% | no clear edge over ordinary days |
| 30 days | 83 | +0.74% | +3.4% | 53% | 56% | no clear edge over ordinary days |
At the other horizons: 7 days, typical +0.36% over 244 cases; 30 days, typical +0.74% over 83 cases.
By year, the typical move ranged from −0.62% in 2021 to +1.6% in 2017; 8 of 10 years leaned the same way as the whole.
Year by year
| Year | Cases | Typical move | Higher | Lower |
|---|---|---|---|---|
| 2017 | 24 | +1.6% | 62% | 38% |
| 2018 | 66 | −0.39% | 44% | 56% |
| 2019 | 39 | −0.03% | 49% | 51% |
| 2020 | 64 | −0.29% | 47% | 53% |
| 2021 | 101 | −0.62% | 40% | 60% |
| 2022 | 47 | −0.03% | 47% | 53% |
| 2023 | 30 | −0.33% | 43% | 57% |
| 2024 | 57 | +0.16% | 53% | 47% |
| 2025 | 43 | −0.39% | 42% | 58% |
| 2026 | 22 | −0.22% | 45% | 55% |
The latest 10 cases
| Day | What happened | 1 day | 7 days | 30 days |
|---|---|---|---|---|
| The altcoins +4.4% that day | −0.37% | +0.56% | open | |
| The altcoins +4.3% that day | −2.1% | −3.0% | open | |
| The altcoins +5.8% that day | −0.47% | −3.6% | open | |
| The altcoins +7.1% that day | +0.45% | +4.0% | open | |
| The altcoins +4.2% that day | +5.8% | +10.5% | open | |
| The altcoins +4.6% that day | −2.0% | −5.8% | +4.3% | |
| The altcoins +9.7% that day | −1.6% | −0.63% | +3.6% | |
| The altcoins +6.3% that day | +7.3% | +9.9% | +11.3% | |
| The altcoins +6.1% that day | +5.3% | +14.0% | +16.7% | |
| The altcoins +4.7% that day | +0.90% | +2.5% | +1.6% |
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 4% altcoin rallies showed no clear edge: right 56% of 62 calls since 2021, against 50% for that side on any day (Jul 6, 2021 – Sep 24, 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 493 cases here.
§ 06 · Verdict
Verdict
as of · plain, with the caveats
In our data Bitcoin ended higher less often than on ordinary days (46% against 53% over 490 days), and both halves of the history lean the same way.
A typical −0.22% hides a wide spread: one case in 10 was beyond +4.1% and one in 10 beyond −4.1%.
Out of sample, calls like it showed no clear edge (right 56% of 62 calls since 2021, against 50% for that side on any day).
Markets change, so what 4% altcoin rallies did from 2017 to 2026 can stop working.
§ 07 · Questions
Questions
as of · answered from the numbers above
- Did Bitcoin usually end lower the day after the altcoins rise 4% or more?
- In 54% of 493 cases from Nov 7, 2017 to Sep 24, 2026.
- Measured the scoreboard's way, day by day, the share higher was 46% against 53% on Bitcoin's own ordinary days.
- How big was the move the next day?
- The middle case moved −0.22% the next day.
- The best 1 in 10 reached +4.1% or more and the worst 1 in 10 −4.1% or less.
- Is this an edge?
- Not on its own: over 493 cases it shows higher less often than on ordinary days, and out of sample, calls like it showed no clear edge (right 56% of 62 calls since 2021, against 50% for that side on any day).
- The −0.22% typical move is the past's, and a past pattern can stop working.
- When did it last happen?
- The latest was on Sep 24, 2026: The altcoins +4.4% that day.
- A day later the move was −0.37%.
- Does it depend on the year?
- No. The typical move was +1.6% in 2017 (24 cases) and −0.62% in 2021 (101 cases).