CAGR Explained: How to Measure Real Investment Returns

Investing Basics Guide

If someone tells you their portfolio returned an average of 10% per year, that number might be completely misleading. Average returns hide the reality of how your money actually grew. CAGR, or Compound Annual Growth Rate, gives you the true picture.

What Is CAGR?

CAGR is the annual growth rate that takes you from a starting value to an ending value over a specific time period, assuming the gains are compounded each year. It smooths out the bumps and tells you the single annual rate that would have produced the same result.

CAGR = (Ending Value / Beginning Value) ^ (1 / Years) - 1

For example, if you invested $10,000 and it grew to $21,589 over 10 years:

CAGR = ($21,589 / $10,000) ^ (1/10) - 1 = 0.08 = 8%

This tells you the investment grew at a steady 8% per year, compounded, to reach that final value.

Why Average Returns Are Misleading

Here is the problem with averages. Suppose you invest $10,000 and get these returns over two years:

• Year 1: +50%
• Year 2: -33.3%

The average annual return is (+50% + -33.3%) / 2 = +8.35%. That sounds decent. But what actually happened to your money?

• After Year 1: $10,000 x 1.50 = $15,000
• After Year 2: $15,000 x 0.667 = $10,000

You ended exactly where you started. Your real return was 0%, not 8.35%. The CAGR correctly shows this: ($10,000 / $10,000) ^ (1/2) - 1 = 0%.

This is not a contrived example. It happens constantly in real markets. A fund that loses 50% one year and gains 50% the next has an average return of 0% but a CAGR of -13.4%. You lost money despite "average" returns of zero.

How to Calculate CAGR Step by Step

1. Find your starting investment value.
2. Find your ending investment value.
3. Count the number of years between start and end.
4. Divide the ending value by the starting value.
5. Raise the result to the power of (1 / number of years).
6. Subtract 1 and multiply by 100 to get the percentage.

Or skip the math and use our CAGR Calculator to get instant results.

CAGR Benchmarks

Knowing your CAGR is useful only if you have something to compare it against. Here are the long-term benchmarks:

If your portfolio CAGR is below 7% over a 10+ year period, a simple S&P 500 index fund would have done better after inflation.

Comparing Investments Using CAGR

CAGR makes it easy to compare investments with different time frames and starting amounts. Suppose you are comparing two funds:

• Fund A: Grew from $5,000 to $12,000 in 8 years. CAGR = 11.6%.
• Fund B: Grew from $20,000 to $38,000 in 6 years. CAGR = 11.3%.

Despite the different dollar amounts and time frames, CAGR puts them on equal footing. Fund A slightly outperformed. You can also use the Stock Return Calculator to compare individual stock performance.

Limitations of CAGR

CAGR is powerful but not perfect. Be aware of these blind spots:

It Ignores Volatility

Two investments can have the same CAGR but wildly different paths. One might grow steadily. The other might drop 40% and then recover. CAGR treats them as identical. If you care about the ride (and you should), look at volatility and maximum drawdown alongside CAGR.

It Ignores Cash Flows

CAGR assumes you made one investment at the start and did nothing else. If you added money along the way or withdrew funds, CAGR will not reflect your actual experience. For portfolios with regular contributions, use time-weighted return or internal rate of return instead.

It Ignores Risk

A 15% CAGR from a leveraged crypto portfolio is not the same as a 15% CAGR from a diversified stock fund. CAGR does not tell you how much risk you took to achieve that return. Always consider the Sharpe ratio or risk-adjusted returns when evaluating performance.

It Does Not Predict the Future

A stock with a 20% CAGR over the last 5 years will not necessarily maintain that rate. Past CAGR is a historical measurement, not a forecast. Use it to evaluate what happened, not to predict what will happen.

The Bottom Line

CAGR is the most honest single number for measuring investment performance. It accounts for compounding, strips out the misleading effects of averaging, and allows apples-to-apples comparison between any two investments.

Whenever someone quotes an "average annual return," ask for the CAGR instead. Better yet, calculate it yourself with the CAGR Calculator.