What happens if you miss the 10 best days on the stock market
October 13, 2025
4 min read
What Happens If You Miss the 10 Best Days on the Stock Market?
20 years of market history. About 5,000 trading days. You miss 10 of them — the best ones. Result: your wealth is cut in half. This statistic is the strongest argument against market timing — and for a structure that keeps you invested when fear is at its peak.
10
Days out of 5,000 — and they determine half your return
CHF 170,000
Lost by missing the 10 best days (on CHF 100,000 over 20 years)
7 of 10
Best days fell within 2 weeks of the worst days
Contents
01The statistic that changes everything
From J.P. Morgan Asset Management, based on the S&P 500 over 20 years (2004–2023). You invest CHF 100,000 at the start and stay invested:
| Scenario | End wealth | Return p.a. |
|---|---|---|
| All days invested | CHF 320,000 | ~6.0% |
| Missed 10 best days | CHF 150,000 | ~2.1% |
| Missed 20 best days | CHF 90,000 | −0.5% |
| Missed 30 best days | CHF 57,000 | −2.8% |
Source: J.P. Morgan Asset Management, Guide to the Markets, S&P 500, 2004–2023.
10 days. Out of roughly 5,000. That's 0.2% of all trading days. They make the difference between CHF 320,000 and CHF 150,000. More than half your entire return comes from 10 days.
02The best days come when you least expect them
The uncomfortable truth
7 of the 10 best trading days in the last 20 years fell within 2 weeks of the worst days. The biggest surges happen in the middle of panic — exactly when everyone is selling.
24 March 2020: S&P 500 jumps +9.4% in a single day. Two weeks earlier were the worst crash days since 2008.
13 October 2008: +11.6% in one day. Middle of the biggest financial crisis of our generation.
13 November 2008: +6.9%. One month after the worst crash. Those who stayed invested captured both days.
"You can't plan for the best days. But you can be there — by simply staying invested."
03What this means for market timing
To time successfully, you must be right twice: on the exit and the re-entry. Almost nobody re-enters at the bottom — because at the bottom, fear is at its peak.
How market timing typically plays out
Week 1: Market falls 5%. You watch nervously.
Week 2: Falls another 10%. You sell. "Just in time."
Week 4: Market suddenly surges 8%. You're not invested.
Month 3: Market is nearly back to where you sold.
Month 6: Market is higher than before the crash. You buy back — at a higher price than you sold at.
Result: You sold expensive and bought back even more expensively.
Dalbar (QAIB) has documented this for 30+ years: the average investor earns 1.5 percentage points less per year than the fund they're invested in — the behaviour gap. Market timing is the biggest single driver.
Full behaviour gap analysis: The True Cost of Investing — Layer 3.
04The psychology: Why we sell anyway
Loss aversion: A CHF 1,000 loss feels twice as painful as a CHF 1,000 gain feels good. A 20% crash doesn't feel "temporary" — it feels existential.
Recency bias: After three weeks of falling prices, it "feels" like the market will never recover. 100 years of data showing otherwise are abstract. The red number in the app is concrete.
Action bias: In a crisis, doing nothing feels passive and irresponsible. Selling feels decisive. But with investments, doing nothing is almost always the better decision.
How to structurally bypass these traps: Master Your Emotions.
05The solution: Stay invested + savings plan + automation
1. Stay invested. Not because it feels good. Because the 10 best days come in the middle of crises — and you only capture them if you're in the market.
2. Automatic savings plan. Same amount every month, by standing order. No decision, no headline-dependency. The plan automatically buys cheaper after a drop.
3. Understand what you own. Someone who owns 1,500 anonymous companies in an ETF sells more easily in panic than someone who knows: "I own Nestlé, Visa, LVMH — they make money even in a crisis."
06How arvy implements this structurally
Stay invested: No "Sell" button in the foreground. No daily push notifications. Quarterly reports and Weekly newsletter instead.
Automatic savings plan: From CHF 1/month. Money flows, gets invested, portfolio stays balanced. No manual trade needed.
Quality you understand: ~30 global quality companies. Every quarter we explain why we hold what we hold.
07Frequently asked questions
What happens if I miss the 10 best days?
Your end wealth is cut in half. CHF 320,000 becomes CHF 150,000. 10 days out of 5,000 make the difference.
When do the best trading days occur?
Almost always during crises. 7 of the 10 best days fell within 2 weeks of the worst days.
Can I predict the best days?
No. No model can reliably predict them. The only strategy: stay invested.
What is the behaviour gap?
~1.5% per year in lost returns from emotional mistakes. Documented by Morningstar and Vanguard.
Savings plan or lump sum?
Statistically, lump sum wins 2/3 of the time. Psychologically, the savings plan is better for most.
What should I do when the market crashes?
Nothing. The savings plan buys cheaper automatically. In 2020, everything recovered within 5 months.
Further reading
10 days. 0.2% of all trading days. And they make the difference.
Market timing fails not from lack of intelligence. It fails because the best days come in the middle of the worst fear. The solution isn't to be braver. It's to have a structure that makes bravery unnecessary.
Written by Thierry Borgeat, reviewed by Patrick Rissi, CFA and Florian Jauch, CFA. "10 Best Days" from J.P. Morgan Asset Management, S&P 500, 2004–2023. Behaviour gap from Morningstar "Mind the Gap". Last updated April 2026.
Disclaimer: Historical returns are not a guarantee of future results. arvy is a FINMA-supervised asset manager with a CISA licence. Imprint & Legal Information.
