What happens if you miss the stock market's best months?
The short answer
In a hypothetical illustration, $1,000 in US stocks on the first trading day of 2000 grew to $8,736 by June 30, 2026. Missing only the single best six-month stretch in those 26 years, and sitting in cash instead, left $5,699, which is 35% less wealth. The best stretches arrived when staying invested felt hardest, and there's no reliable way to know them in advance.
What $1,000 became from 2000 through June 2026
This hypothetical starts with $1,000 in US stocks at the beginning of 2000. In each missed scenario, the money sits in cash at a 0% return for the best stretch of that length, then goes fully back in.
- Fully invested: $8,736
- Missed the best week (November 21 to 28, 2008, up 19.5%): $7,310
- Missed the best month (March 24 to April 22, 2020, up 25.1%): $6,983
- Missed the best 3 months (March 24 to June 22, 2020, up 42.3%): $6,141
- Missed the best 6 months (March 10 to September 4, 2009, up 53.3%): $5,699
Why a few weeks make such a big difference
A handful of short stretches do a disproportionate share of the long-term work. In this sample the best week returned 19.5% and the best six months returned 53.3%.
Both arrived when staying invested felt hardest. The best week came in November 2008 and the best six months started in March 2009.
Why the best weeks can't be timed
There's no reliable way to step aside for the bad days and still be invested for the good ones. The weeks that repair a decline often show up inside the decline, which is why sitting in cash is so expensive.
November 2008 and April 2020 were two of the hardest months to stay invested, and also two of the most expensive to miss.
How the numbers were calculated
The figures are a hypothetical illustration of $1,000 invested in the Fama/French Total US Market Research Index from January 3, 2000 through June 30, 2026, with dividends reinvested and no taxes, fees, or withdrawals. The missed windows are the single best 5, 21, 63, and 126 trading-day stretches in the sample.
The Fama/French indices represent academic concepts and aren't available for direct investment. Returns don't reflect the expenses of an actual portfolio, and past performance doesn't guarantee future results.
Takeaway
In this illustration, missing a single six-month stretch of US stock returns since 2000 left 35% less wealth, and that stretch came when staying invested felt hardest.
Related questions
What was the stock market's best week since 2000?
In this sample it was November 21 to 28, 2008, when US stocks returned 19.5%. Missing that week alone would have turned $8,736 into $7,310.
Why not wait in cash until the market calms down?
The weeks that repair a decline often show up inside the decline. The best month in this sample ran from March 24 to April 22, 2020, one of the hardest times to stay invested.
Sources
Index data from Kenneth R. French’s data library. Fama/French Total US Market Research Index, January 3, 2000 through June 30, 2026.
Disclosures
Disclosures. This material is provided by Cornerstone Wealth Partners for educational and informational purposes only and does not constitute investment, legal, or tax advice, nor a recommendation to buy or sell any security. Figures are a hypothetical illustration of $1,000 invested in the Fama/French Total US Market Research Index from January 3, 2000 through June 30, 2026, with dividends reinvested and no taxes, fees, or withdrawals. “Missed” scenarios assume the hypothetical portfolio is fully converted to cash (0% return) for the single best consecutive 5, 21, 63, or 126 trading-day window in the sample, then fully reinvested. Best windows: 5 days ending November 28, 2008; 21 days ending April 22, 2020; 63 days ending June 22, 2020; 126 days ending September 4, 2009. Index data from Kenneth R. French’s data library. The Fama/French indices represent academic concepts and are not available for direct investment; returns do not reflect the expenses of an actual portfolio. Past performance is not indicative of, or a guarantee of, future results. Investing involves risk, including possible loss of principal. Cornerstone Wealth Partners is a registered investment adviser; registration does not imply any particular level of skill or training.
This article is for educational purposes only and is not personalized investment, tax, or legal advice. Talk with a qualified professional about your situation.