Mean reversion · daily rule · Energy & power
Bollinger Reversion on Eos Energy
What the play says
EOSE with the play, last two years
Shading shows the play's call from the close that triggered it.
Growth of $10,000 since 2020
Log scale. After trading costs, with T-bill interest while out.
The record
The play against buying and holding EOSE over exactly the same dates, after costs.
| Play, since 2020 | Hold, since 2020 | Play, 5 yrs | Hold, 5 yrs | |
|---|---|---|---|---|
| Annual return | −15.1% | −26.3% | −20.5% | −28.9% |
| Total return | −61% | −83% | −68% | −82% |
| Worst drawdown | −86.9% | −97.9% | −86.9% | −94.9% |
| Volatility | 60.5% | 116.4% | 62.0% | 118.8% |
| Sharpe ratio | −0.02 | 0.28 | −0.12 | 0.27 |
| Time invested | 28% | 100% | ||
| Switches per year | 8.2 | 0 |
Every call, graded
Right on 25 of 48 closed calls (52%). In calls averaged −0.9%; out calls saw EOSE move +9.1% on average.
| Called | Call | Price | Until | EOSE moved | Result |
|---|---|---|---|---|---|
| Jun 17, 2026 | OUT | $7.60 | now | −69.5% | open |
| Jun 9, 2026 | IN | $6.26 | Jun 17, 2026 | +21.4% | ✓ right |
| Apr 9, 2026 | OUT | $5.95 | Jun 9, 2026 | +5.2% | ✕ wrong |
| Feb 4, 2026 | IN | $12.40 | Apr 9, 2026 | −52.0% | ✕ wrong |
| Jun 24, 2025 | OUT | $4.37 | Feb 4, 2026 | +183.8% | ✕ wrong |
| May 29, 2025 | IN | $4.51 | Jun 24, 2025 | −3.2% | ✕ wrong |
| Apr 11, 2025 | OUT | $4.23 | May 29, 2025 | +6.7% | ✕ wrong |
| Apr 7, 2025 | IN | $3.54 | Apr 11, 2025 | +19.5% | ✓ right |
| Mar 5, 2025 | OUT | $4.97 | Apr 7, 2025 | −28.8% | ✓ right |
| Feb 24, 2025 | IN | $4.26 | Mar 5, 2025 | +16.7% | ✓ right |
| Nov 25, 2024 | OUT | $2.79 | Feb 24, 2025 | +52.7% | ✕ wrong |
| Nov 6, 2024 | IN | $2.55 | Nov 25, 2024 | +9.4% | ✓ right |
An in call is right when the price rose before the next call; an out call is right when it fell. The latest 12 of 49 calls shown.
How the play works
- In on a close below the lower band (20-day average − 2 standard deviations).
- Out on a close above the 20-day average.
This runs against Bollinger's advice that tags of the bands are not signals. It is shown because so many traders use it.
The case against
Valeriy Zakamulin tested moving-average timing on up to 155 years of U.S. stock data and found no statistically significant edge in the second half of that record. The rules earned their keep in a few severe bear markets and lagged buy and hold for long stretches in between.