One rule, one stock, once a month
The Catsup Bot
Prices through Sep 30, 2026 · updated each weekday morning, last pulled 2026-10-03 · rebalanced monthly · paper money
Backtest, price only, survivorship-biased by construction. Read the caveats below before believing the chart.
Current holding
Paper money$5,000 notional since Oct 1, 2026. No real account, no real orders.Holding
TSLA
since the Sep 30, 2026 close
Entry
$354.81
14.092 shares · $0.01 cash
Value
$5,222.36
at Oct 2, 2026 close
P&L
+$222.36
+4.45%
Next decision: the October 2026 close. The rebalance script is dry-run by default and only ever writes to a JSON ledger that a human reviews. It has no broker connection.
Backtest, September 2022 to September 2026
- Buy the worst (the rule) 14×
- Dan's version (1/2/3-month) 5.6×
- Buy the best (control) 3.9×
- Equal-weight Mag 7 4×
- SPY 2.1×
Growth of one dollar from the Sep 30, 2022 close, log scale, rebalanced at every month-end close. Price returns only.
| Strategy | Sep 2022 → Sep 2026 | Annualized | Since June 2013 | Annualized |
|---|---|---|---|---|
| Buy the worst (the rule) | +1,341% | +94.8% | +17,384% | +47.7% |
| Dan's version (1/2/3-month) | +461% | +53.9% | +3,245% | +30.3% |
| Buy the best (control) | +290% | +40.5% | +20,564% | +49.5% |
| Equal-weight Mag 7 | +305% | +41.8% | +5,755% | +36.0% |
| SPY | +114% | +20.9% | +375% | +12.5% |
48 and 159 monthly holding periods respectively. Equal-weight rebalances to equal dollars every month. SPY is buy and hold. Price returns only.
Ranks at the Sep 30, 2026 close
| Symbol | 3-mo return | 6-mo return | 12-mo return | Rank 3m | Rank 6m | Rank 12m | Avg rank |
|---|---|---|---|---|---|---|---|
TSLA the pick — worst average rank | −15.6% | −4.6% | −20.2% | 1 | 1 | 1 | 1.00 |
AMZN | +4.5% | +19.6% | +13.5% | 3 | 2 | 4 | 3.00 |
GOOGL | −3.7% | +19.7% | +41.5% | 2 | 3 | 7 | 4.00 |
META | +28.7% | +26.8% | −1.3% | 6 | 4 | 2 | 4.00 |
NVDA | +14.1% | +31.0% | +22.4% | 4 | 5 | 5 | 4.67 |
AAPL best average rank (the control) | +15.1% | +31.2% | +30.8% | 5 | 6 | 6 | 5.67 |
MSFT | +37.5% | +38.6% | −1.0% | 7 | 7 | 3 | 5.67 |
Rank 1 is the worst return in that horizon. Ties on the average go to the worse 12-month return. Price returns from month-end closes, no dividends.
Dan's version (1/2/3-month) would pick AMZN.
Read this before believing the chart
- Survivorship. These seven stocks were named the Magnificent Seven in 2023 because they had already won. Any rule that only ever holds one of them inherits that head start. Nobody was running this on this list in 2022.
- Tiny sample. The headline backtest is 48 monthly bets. That is not enough to separate a good rule from a lucky one.
- Bear-market bottom. The window opens at the September 2022 close, within weeks of the 2022 low. Almost anything long and aggressive looks good from there.
- Price only. No dividends, no trading costs, no slippage, no taxes. Month-end closes from Yahoo Finance, split-adjusted.
- It works until it doesn't. Over the full history the bot can see, from June 2013, buying the best average rank beat buying the worst (+20,564% vs +17,384%). The recent window is where the rule shines. That is a reason to watch it, not to trust it.
The rule
At each month-end close, rank AAPL, MSFT, GOOGL, AMZN, META, NVDA, TSLA by trailing 3-, 6-, 12-month price return, average the three ranks, and hold the single worst for the next month.
The rule is Sheel Mohnot's, from his post on buying the worst Mag 7 stock each month. The name took three tries. On Ep 59 Dan said you're “constantly buying the catch-up,” meaning the straggler of the Mag 7 that has to catch up to the rest. The transcript heard “buying the ketchup,” so the bot launched as the Ketchup Bot, and on Ep 61 we learned the name had come out of a transcription error. So now it's the Catsup Bot: the same condiment under its other name, one more step away from what Dan actually said. Dan remembered the lookbacks as 30, 60 and 90 days, so his 1/2/3-month version runs alongside as a comparison. Ties on the average go to the worse 12-month return. This page closes the Ep 17 paper-trading promise: the bot is the paper account.
Pick log
Paper ledger
| Month-end | Action | Holding | Price | Shares | Cash |
|---|---|---|---|---|---|
| Sep 30, 2026 | Opened | TSLA | $354.81 | 14.092 | $0.01 |
Every row is a hand-reviewed entry in a JSON file. Shares are fractional, floored to four decimals. Paper money; no order was placed anywhere.
What the rule would have held, Oct 2022 to Sep 2026
Times picked: MSFT 13 · TSLA 11 · AAPL 9 · META 8 · AMZN 3 · GOOGL 3 · NVDA 1
Every month-end pick since Sep 2022 (48 rows)
| Ranked at | Held through | Holding | Avg rank | Month return |
|---|---|---|---|---|
| Aug 31, 2026 | Sep 2026 | META | 1.67 | +26.7% |
| Jul 31, 2026 | Aug 2026 | META | 1.67 | +2.8% |
| Jun 30, 2026 | Jul 2026 | MSFT | 1.33 | +24.6% |
| May 31, 2026 | Jun 2026 | META | 1.33 | −10.9% |
| Apr 30, 2026 | May 2026 | MSFT | 1.67 | +10.4% |
| Mar 31, 2026 | Apr 2026 | MSFT | 1.00 | +10.2% |
| Feb 28, 2026 | Mar 2026 | MSFT | 1.67 | −5.7% |
| Jan 31, 2026 | Feb 2026 | MSFT | 1.33 | −8.7% |
| Dec 31, 2025 | Jan 2026 | META | 2.00 | +8.5% |
| Nov 30, 2025 | Dec 2025 | META | 1.33 | +1.9% |
| Oct 31, 2025 | Nov 2025 | META | 1.00 | −0.1% |
| Sep 30, 2025 | Oct 2025 | AMZN | 2.00 | +11.2% |
| Aug 31, 2025 | Sep 2025 | AAPL | 2.33 | +9.7% |
| Jul 31, 2025 | Aug 2025 | AAPL | 1.33 | +11.8% |
| Jun 30, 2025 | Jul 2025 | AAPL | 1.67 | +1.2% |
| May 31, 2025 | Jun 2025 | AAPL | 1.33 | +2.2% |
| Apr 30, 2025 | May 2025 | GOOGL | 2.00 | +8.1% |
| Mar 31, 2025 | Apr 2025 | MSFT | 2.67 | +5.3% |
| Feb 28, 2025 | Mar 2025 | MSFT | 1.67 | −5.4% |
| Jan 31, 2025 | Feb 2025 | MSFT | 1.33 | −4.4% |
| Dec 31, 2024 | Jan 2025 | MSFT | 1.00 | −1.5% |
| Nov 30, 2024 | Dec 2024 | MSFT | 1.33 | −0.5% |
| Oct 31, 2024 | Nov 2024 | MSFT | 1.00 | +4.2% |
| Sep 30, 2024 | Oct 2024 | GOOGL | 2.00 | +3.2% |
| Aug 31, 2024 | Sep 2024 | MSFT | 2.33 | +3.2% |
| Jul 31, 2024 | Aug 2024 | MSFT | 2.33 | −0.3% |
| Jun 30, 2024 | Jul 2024 | TSLA | 2.00 | +17.3% |
| May 31, 2024 | Jun 2024 | TSLA | 1.00 | +11.1% |
| Apr 30, 2024 | May 2024 | AAPL | 1.33 | +12.9% |
| Mar 31, 2024 | Apr 2024 | TSLA | 1.00 | +4.3% |
| Feb 29, 2024 | Mar 2024 | TSLA | 1.00 | −12.9% |
| Jan 31, 2024 | Feb 2024 | TSLA | 1.00 | +7.8% |
| Dec 31, 2023 | Jan 2024 | AAPL | 2.00 | −4.2% |
| Nov 30, 2023 | Dec 2023 | TSLA | 2.00 | +3.5% |
| Oct 31, 2023 | Nov 2023 | AAPL | 1.67 | +11.2% |
| Sep 30, 2023 | Oct 2023 | AAPL | 1.67 | −0.3% |
| Aug 31, 2023 | Sep 2023 | AAPL | 2.33 | −8.9% |
| Jul 31, 2023 | Aug 2023 | AMZN | 2.33 | +3.2% |
| Jun 30, 2023 | Jul 2023 | GOOGL | 1.00 | +10.9% |
| May 31, 2023 | Jun 2023 | TSLA | 1.00 | +28.4% |
| Apr 30, 2023 | May 2023 | TSLA | 1.00 | +24.1% |
| Mar 31, 2023 | Apr 2023 | TSLA | 2.33 | −20.8% |
| Feb 28, 2023 | Mar 2023 | AMZN | 1.33 | +9.6% |
| Jan 31, 2023 | Feb 2023 | TSLA | 1.33 | +18.8% |
| Dec 31, 2022 | Jan 2023 | TSLA | 1.00 | +40.6% |
| Nov 30, 2022 | Dec 2022 | META | 1.33 | +1.9% |
| Oct 31, 2022 | Nov 2022 | META | 1.00 | +26.8% |
| Sep 30, 2022 | Oct 2022 | NVDA | 1.33 | +11.2% |