If You Invest Just $50 per Month in the Stock Market, Here's What History Says It Could Be Worth in 20 Years
Key Points
Over many decades, the S&P 500 has averaged annual gains of close to 10%.
Over the coming 10 and 20 years, it could deliver higher or lower growth rates.
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If you're looking to build a hefty nest egg and you'd like to do it by investing in stocks, that's a fine idea, and an achievable goal, as well. Many, including Warren Buffett, would recommend doing so via a low-fee index fund that tracks the S&P 500 Index (SNPINDEX: ^GSPC). One such well-regarded fund is the Vanguard S&P 500 ETF (NYSEMKT: VOO). (It's an exchange-traded fund, or ETF, by the way -- a fund that trades like a stock.)
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How might your money grow over time if you invest in this Vanguard ETF? Well, no one can know for sure, but a look at how it has performed in the past could help you make an informed estimate:
|
Period |
Average Annual Gain |
|---|---|
|
Past 3 years |
22.94% |
|
Past 5 years |
13.55% |
|
Past 10 years |
15.32% |
|
Past 15 years |
15.65% |
Data source: Morningstar.com, as of Oct. 1, 2026.
Looking at the table above, you might think that a 15% average annual growth rate seems reasonable, but know that the S&P 500 has averaged annual returns closer to 10% (ignoring inflation) over many decades. I might even use a lower average annual gain, considering how much the stock market has run up in recent years -- after all, a stock market crash or correction is not out of the question in the coming year or two.
So check out the table below, which shows how your money might grow at several different growth rates if you invest just $50 per month (or $600 per year).
|
Years Investing $50 per Month ($600 annually) |
Growing at 8% Annually |
Growing at 10% Annually |
Growing at 12% Annually |
|---|---|---|---|
|
10 years |
$8,692 |
$9,562 |
$10,529 |
|
20 years |
$27,457 |
$34,365 |
$43,231 |
|
30 years |
$67,970 |
$98,696 |
$144,800 |
|
40 years |
$155,434 |
$265,556 |
$460,255 |
Data source: Calculations via Investor.gov's calculator.
Of course, the more you can invest and the longer you can remain invested, the more money you can amass.
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Selena Maranjian has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Vanguard S&P 500 ETF. The Motley Fool has a disclosure policy.
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