Is extreme greed a sell signal?
A Fear and Greed reading of 80 or above means the market is euphoric and due to fall.
Where we are now. Today the index reads 62, against a threshold of 80. Shaded bands are the 5 occasions the rule fired, the same ones counted in the table below: 2019-06, 2020-08, 2021-10, 2024-02, 2024-11.
This rule has fired 5 times. A 40% fall followed within a year on 2 of the 5. On comparable days when it did not fire, a 40% fall followed 40.2% of the time.
| Times it fired | 5 | separate occasions, not days |
|---|---|---|
| What followed | 40.0% | a 40% fall within 365 days of that close |
| Could plausibly be | 14% to 73% | the range the true rate could take, on this many occasions, before you invoke anything but chance; a binomial interval that treats the episodes as independent trials |
| Happened anyway | 40.2% | comparable days when the rule did not fire |
| Difference | -0.2 pts | near zero means the signal added nothing |
Where the claim comes from
The other half of the same index, and the other half of the same advice.
How we tested it
Trigger: index at 80 or above. Scored as a top rule: did a 40% fall follow within 365 days?
Only days the rule could have fired are counted. Consecutive triggers within 90 days are one occasion. The baseline excludes each trigger and the 90 days after it, because the aftermath of a signal is not a fair comparison. No verdict is given below 20 occasions.
What the numbers say
Five occasions. 40.0% followed by a 40% fall within a year, against 40.2% on comparable days when the rule did not fire: a 0.2-point gap, negative, on 5 observations. A one-point difference, which is nothing at all, on five episodes.
What this does not mean
A result this flat is easy to over-read in the other direction. It does not show the index is useless; it shows this specification, on this sample, found no difference.
And it does not mean the threshold itself was chosen fairly. Every rule in this registry was specified by someone who had already seen bitcoin’s history, so the cut-off is fitted to the record it is being judged against. The interval above measures sampling variation between independent trials and nothing else: not the choice of threshold, not that cycle turns are few and related, and not that thirty-six rules were tested in total. Only the forward record, which fixes a rule before its answer is known, avoids this.
What would change the answer
More history. The index is the youngest series on this site.
If you cannot time it, the question changes
Most of the claims in this registry cannot be shown to beat a coin flip, and several are worse than one. That is not an argument against holding bitcoin. It is an argument that the decision worth spending effort on is how much to hold, not when to buy.
That is what How much bitcoin? is for: what fixed weights actually did in a conventional portfolio, and how much the answer depended on the year you started. For the valuation state today, and what has historically followed readings like it, see Where Things Stand.
Recomputed from the daily public snapshot by fetch/scorecard.py and published as scorecard.json. Method on the methods page; every claim in the scorecard.