Research · Altcoins
Large-cap alts pooled against Bitcoin
Last reviewed 2026-09-21Source: CoinGecko historical price and market-capitalisation data, with the basket rule stated belowBasket construction and methodology only. No correlation, beta or return figure is asserted on this page.
Dataset, period, method and limitations
The basket is built from CoinGecko's historical price and market-capitalisation series. The period runs from the first date on which at least five non-Bitcoin assets each held a market capitalisation above the inclusion threshold, through the most recent complete calendar year. The method is a fixed-rule, equal-weighted index of the qualifying assets, rebalanced on a stated schedule, with the ratio of the index to Bitcoin reported by phase.
The limitations are the reason this section comes first. A pooled comparison has four decisions embedded in it, and each one can change the answer: which assets qualify, how they are weighted, when the basket is rebalanced, and how assets that leave the qualifying set are handled. This page states all four. A reader who disagrees with any of them can reconstruct the comparison under different rules, and should.
The most serious limitation is survivorship. The assets that are large today are, by construction, the ones that survived and grew. Assets that were large at the start of the period and then declined are not in today's basket, and if the basket is defined from today's membership backwards, the comparison is biased upward. This page handles that by defining membership at each rebalance date from the data available at that date, and by stating that the resulting series still cannot fully correct for assets that were never listed on the venues the data covers.
The basket definition
| Decision | Rule applied | Why this rule |
|---|---|---|
| Inclusion | Non-Bitcoin assets whose market capitalisation exceeded the threshold at the rebalance date, ranked by capitalisation, capped at a fixed count | A rank-and-threshold rule is reproducible from published data and does not require a judgement about which projects are interesting |
| Weighting | Equal weight across the qualifying assets | Equal weighting avoids letting the largest member dominate the basket, which would make the index a proxy for one asset rather than for the group |
| Rebalancing | Quarterly, on the first day of each calendar quarter | A fixed calendar schedule is auditable and avoids the temptation to rebalance around events |
| Exits | An asset that falls below the threshold is removed at the next rebalance; its return up to that point is retained in the series | Retaining the return avoids the look-ahead bias that comes from dropping an asset once it is known to have failed |
Last reviewed 2026-09-21Source: Basket rule defined by this site; membership data from CoinGeckoThe rule is stated so it can be reproduced. No index level or return figure is published on this page.
The weighting choice deserves a note. A capitalisation-weighted basket would be dominated by whichever non-Bitcoin asset happened to be largest, and over much of the period that would have made the index a proxy for a single network. Equal weighting gives each qualifying asset the same influence, which is the right choice when the question is how the group behaves rather than how the largest member behaves. The cost is that equal weighting implicitly assumes periodic rebalancing, which is a trading activity with its own costs, and this page does not model those costs.
The exit rule is the one that most affects the result. If an asset is dropped from the basket at the moment it is known to have failed, the index never experiences the failure, and the comparison is biased upward by exactly the amount of the omitted decline. Retaining the return up to the removal date removes most of that bias, though not all of it: an asset that was never listed on a covered venue is invisible to the data and therefore invisible to the basket.
How the basket behaves against Bitcoin
Across the observable period, the pooled ratio has followed the rotation pattern described on the cycle comparison page: the basket's ratio to Bitcoin compresses during the late stages of a Bitcoin advance and expands during the early stages of a recovery. That is the aggregate version of the pattern the individual pages in this cluster describe, and it is more robust than any single asset's version of it, because pooling averages out the asset-specific noise.
The pooled series also shows something the individual series do not: the dispersion within the basket is large. In any given quarter, the best and worst members of the basket can differ enormously in their ratio to Bitcoin, and the pooled figure is an average of those divergent paths. A reader who takes the pooled result as a statement about any particular asset will be wrong most of the time. The individual pages in this cluster exist precisely because the pooled view hides the differences that matter.
The comparison with Bitcoin's own drawdown behaviour is set out on the drawdown reference. The relevant point here is that the basket's drawdowns have been deeper than Bitcoin's in every completed cycle in the period, and its recovery periods longer. That is a statement about the record, and it is consistent with the basket containing smaller, less liquid assets than BTC. The liquidity page explains the mechanism.
What a pooled comparison can and cannot show
A pooled comparison can show that the top of the non-Bitcoin market behaves differently from Bitcoin in a consistent direction across cycles. It can show that the difference is larger in some phases than others. It can show that the dispersion within the group is large enough that the group average is a weak description of any member.
It cannot show why. The basket's ratio to Bitcoin moves with the market's risk appetite, with the composition of the basket, and with the liquidity available to each member. Those three are entangled, and the price data does not separate them. A claim that the basket underperformed because of a change in the market's structure is an association, not a finding, and this page does not make it.
It also cannot show what will happen next. The pattern described above is a description of a small number of completed cycles. The number of observations is small enough that a single unusual cycle would change the picture, and the composition of the basket changes over time in ways that make the early and late parts of the series not strictly comparable. The return profiles page makes the same point about Bitcoin's own record: the shape of returns has changed across cycles, which is a reason to be cautious about extrapolating any of it.
Sources and references
The basket rule is defined by this site and stated in full above so it can be reproduced. The membership and price data come from CoinGecko's historical series. The cycle phase dates come from this site's own cycle reference.
- Historical price and capitalisation series. CoinGecko, Bitcoin historical data and the corresponding series for each basket member: the daily USD prices and capitalisation figures behind the index.
- Market capitalisation as a measure. This site, Market Cap Explained: why the inclusion threshold rests on a constructed figure, and where that construction misleads.
- Bitcoin's share of the total. This site, Bitcoin Dominance: the aggregate measure that a basket comparison is implicitly related to.
- Cycle phases. This site, Bitcoin Cycle Comparison: the phase dates used as the reference frame for the description above.
- Liquidity and amplification. This site, Bitcoin Liquidity: why a basket of smaller assets moves further than BTC in the same window.
Related reading
- Research HubEvery dataset on the site, with methodology and provenance.
- Altcoin ResearchAltcoins measured against Bitcoin: design intent, consensus, execution, scaling and market structure.
- The ETH-BTC Correlation RecordHow the correlation is measured, how it behaves across windows, and where it breaks down.
- The ETH/BTC RatioWhat the ratio measures, how to read its trend, and why it is not a forecast.
- ETH During Bitcoin Bull PhasesAssociation within a common market factor, and what co-movement cannot establish.
- ETH During Bitcoin Bear PhasesDrawdown depth and duration compared over identical windows, and the limits of the comparison.