Mean reversion · daily rule · Software & devices
Mayer Multiple on Nebius Group
What the play says
NBIS with the play, last two years
Shading shows the play's call from the close that triggered it.
Growth of $10,000 since 2025
Log scale. After trading costs, with T-bill interest while out.
The record
The play against buying and holding NBIS over exactly the same dates, after costs.
| Play, since 2025 | Hold, since 2025 | Play, 5 yrs | Hold, 5 yrs | |
|---|---|---|---|---|
| Annual return | +143.9% | +151.6% | +143.9% | +151.6% |
| Total return | +184% | +195% | +184% | +195% |
| Worst drawdown | −48.3% | −48.3% | −48.3% | −48.3% |
| Volatility | 111.3% | 112.9% | 111.3% | 112.9% |
| Sharpe ratio | 1.29 | 1.31 | 1.29 | 1.31 |
| Time invested | 93% | 100% | ||
| Switches per year | 3.4 | 0 |
Every call, graded
Right on 3 of 4 closed calls (75%). In calls averaged +26.7%; out calls saw NBIS move +2.0% on average.
| Called | Call | Price | Until | NBIS moved | Result |
|---|---|---|---|---|---|
| Oct 17, 2025 | IN | $113.44 | now | +82.4% | open |
| Sep 22, 2025 | OUT | $106.60 | Oct 17, 2025 | +6.4% | ✕ wrong |
| Sep 10, 2025 | IN | $93.39 | Sep 22, 2025 | +14.1% | ✓ right |
| Sep 9, 2025 | OUT | $95.72 | Sep 10, 2025 | −2.4% | ✓ right |
| Aug 8, 2025 | IN | $68.78 | Sep 9, 2025 | +39.2% | ✓ right |
An in call is right when the price rose before the next call; an out call is right when it fell. The latest 5 of 5 calls shown.
How the play works
- In while the close is less than 2.4 times its 200-day average.
- Out when it reaches 2.4 or more.
Mayer used it to decide when to keep buying, not when to sell. Selling above 2.4 is Be The Puck's reading.
On ordinary stocks a price 2.4 times the 200-day is rare, so this is close to buy and hold.
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.