Does timing the market work?
No, and the reason is structural rather than moral: it requires being right twice, and the market's best days cluster inside its worst periods, which is exactly when someone who sold is still out.
Missing a small number of the strongest days over a multi-decade span removes a large share of the Total returnPrice change plus income — dividends for shares, coupons for bonds — with the income assumed reinvested. Quoting price change alone understates long-run equity returns by roughly the dividend yield each year.. That statistic gets quoted as though it were about luck. It is not — those days are not scattered randomly. They arrive in the middle of falls, often within weeks of the worst days, because VolatilityHow much returns scatter around their average, usually measured as a standard deviation. It is a proxy for risk rather than risk itself: it treats an unexpected gain and an unexpected loss identically. clusters.
So the trade is not 'sell high, buy back low'. It is 'sell during a fall, then buy back during a fall that feels worse', which is a decision almost nobody makes. The measured result is the behaviour gap: the return investors actually earn is lower than the return of the funds they hold, and the difference is timing.
The decision simulator on this site exists to make this arguable rather than assertable — you play twenty years of real market history, seeing only what an investor at the time would have seen, and get scored against having done nothing.
When the answer is different
- Rebalancing to a target allocation is not market timing, even though it involves selling — it responds to your portfolio drifting, not to a forecast.
- Reducing risk because your circumstances changed — a job loss, a shorter horizon — is a change of plan, not a bet on direction.
Put your own numbers to it
Every answer here is general. These are not.
- The cost of being out
What does missing the best years cost?
- The decision simulator
How would I actually behave in a crash?
The research this rests on
Each note states its claim, rates how strong the evidence actually is, and lists the conditions under which it fails.
- Market timing requires being right twice, and the good days cluster in the bad times
Being out of the market for a small number of the strongest periods removes a large share of long-run returns, and those periods occur disproportionately during drawdowns. (moderate)
- Investors underperform the funds they own
The return the average investor earns is measurably lower than the return of the funds they hold, because of when they buy and sell. (strong)
- Losses hurt about twice as much as equivalent gains feel good
People weight losses substantially more heavily than equal-sized gains, which systematically distorts investment decisions. (strong)
Terms used on this page
The same definitions the underlined words open, written out so nothing on this page depends on a click.
- Total return
- Price change plus income — dividends for shares, coupons for bonds — with the income assumed reinvested. Quoting price change alone understates long-run equity returns by roughly the dividend yield each year.
- Volatility
- How much returns scatter around their average, usually measured as a standard deviation. It is a proxy for risk rather than risk itself: it treats an unexpected gain and an unexpected loss identically.