EXPLAINER
Time in the Market, Explained
Published Oct 19, 2026 · Updated Oct 19, 2026
Does missing the 10 best days really cut your returns?
Yes, but not the way the slogan says. On SPY daily closes from Oct 2016 to Oct 2026, $10,000 left alone became $35,938. Missing the 10 best days leaves $18,976, about half the money but only about a third of the gain. It cuts both ways: dodging the 10 worst days ends at $69,944. The catch is the days cluster. Eight of the ten best landed within two weeks of a worst day.
Computed from 2,514 SPY daily closes, Oct 17, 2016 (212.38) to Oct 16, 2026 (763.25). Price return, dividends excluded. Historical, not a projection.
The scenario table
Five ways the same decade could have gone, all computed from the same SPY daily closes:
| Scenario | $10,000 becomes | Per year |
|---|---|---|
| Fully invested | $35,938 | 13.65% |
| Miss the 10 best days | $18,976 | 6.62% |
| Miss the 20 best days | $13,719 | 3.21% |
| Miss the 30 best days | $10,492 | 0.48% |
| Dodge the 10 worst days | $69,944 | 21.48% |
SPY daily closes, Oct 17, 2016 to Oct 16, 2026. Price return, dividends excluded. The full close series behind this chart is the dataset described under Sources and method.
The honest correction
The slogan says missing the 10 best days cuts your returns in half. The computed version is narrower, and it matters: you keep 52.8% of the final value, so the ending balance is roughly halved, but you keep only 34.6% of the gain. Most of what the decade built is gone, even though the headline balance looks half intact. That is why this page prints the gain, not just the balance.
Why the days are so hard to dodge
- 8 of the 10 best days landed within 14 calendar days of one of the 10 worst days.
- 9 of the 10 best days arrived while SPY was 10% or more below its peak.
- March 2020 alone held 6 of the 10 best days and 6 of the 10 worst days.
February to April 2020. The crash and the rebound share the same weeks: selling out of the worst days meant standing aside for the best ones, which arrived days later, still deep below the peak.
The 10 best days
| Date | SPY daily return |
|---|---|
| Apr 9, 2025 | +10.50% |
| Mar 24, 2020 | +9.06% |
| Mar 13, 2020 | +8.55% |
| Apr 6, 2020 | +6.72% |
| Mar 26, 2020 | +5.84% |
| Nov 10, 2022 | +5.50% |
| Mar 17, 2020 | +5.40% |
| Mar 10, 2020 | +5.17% |
| Dec 26, 2018 | +5.05% |
| Mar 2, 2020 | +4.33% |
The 10 worst days
| Date | SPY daily return |
|---|---|
| Mar 16, 2020 | -10.94% |
| Mar 12, 2020 | -9.57% |
| Mar 9, 2020 | -7.81% |
| Apr 4, 2025 | -5.85% |
| Jun 11, 2020 | -5.76% |
| Mar 18, 2020 | -5.06% |
| Apr 3, 2025 | -4.93% |
| Mar 11, 2020 | -4.87% |
| Mar 20, 2020 | -4.87% |
| Apr 1, 2020 | -4.50% |
What this does not prove
Timing is not impossible. It is unforecastable, because nobody gets the list of days in advance. Index math is also not single-stock math: SPY holds hundreds of companies, and a single stock can fail in ways an index does not. And past clustering does not schedule future clusters. The pattern held this decade; it is a description, not a promise.
Sources and method
Computed from 2,514 SPY daily closes published by Nasdaq, from Oct 17, 2016 (close 212.38) to Oct 16, 2026 (close 763.25), covering 2,513 trading days. Each scenario removes the named days from the chain and compounds the rest. Price return only; dividends are excluded, which understates every scenario. The verification output is retained with the Time in the Market carousel build, and every figure on this page matches it.
Read the carousel
Keep reading
- Compound Interest, Explained: what does starting ten years late actually cost you?
- TSM Deep Dive: a record quarter, and the stock fell. What are we watching?
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