Market What If
Investing's biggest "what ifs" — answered with decades of real market data. No hype, no guru talk. Just the numbers.
Lab The Experiments
Every what-if is backtested on real historical prices, published with its full table.
What if you traded QQQ on the 200-day moving average?
Buy-and-hold vs selling every time QQQ drops below its 200-day average — $10,000, 2005→2024. The timing rule dodged two crashes… and still lost by $64,000.
What if you bought last year's hottest stock, every year, for 20 years?
$1,000 into SPY every January vs $1,000 into the S&P 500's best performer of the previous year. Chasing winners feels smart — the data disagrees.
How How every experiment works
The same lab rules, every time — so you can trust the comparison.
📈 Real prices only. Dividend-and-split-adjusted daily closes, 2005–2024.
🧪 Rules written before the test. No cherry-picking dates or tweaking after seeing results.
📋 Full tables published. Year-by-year numbers on every experiment page — check our math.
🚫 No financial advice. These are historical experiments, not recommendations.