CAGR vs average annual return
By the CAGR Calculator team · Published
Quick answer
The average annual return adds up each year’s return and divides by the number of years (an arithmetic mean). CAGR is the constant rate that actually links the start and end values (a geometric mean). When returns vary, the average is always higher: gaining 50% then losing 50% averages 0%, but the CAGR is −13.40% — you really lost money.
- Average annual return
- Sum of yearly returns ÷ number of years
- CAGR
- (End ÷ Start)^(1 ÷ Years) − 1
- +50% then −50%
- Average 0% · CAGR −13.40%
- Rule of thumb
- CAGR ≈ average − (volatility² ÷ 2)
- Use for real growth
- CAGR
A five-year example
$10,000 is invested and earns these returns:
| Year | Return | Value at year end |
|---|---|---|
| 1 | +20% | $12,000 |
| 2 | −10% | $10,800 |
| 3 | +30% | $14,040 |
| 4 | −25% | $10,530 |
| 5 | +15% | $12,110 |
- Average annual return: (20 − 10 + 30 − 25 + 15) ÷ 5 = 6.00%
- CAGR: (12,110 ÷ 10,000)^(1/5) − 1 = 3.90%
If the investment had really grown 6% every year, it would be worth $13,382 — about $1,270 more than it is. The average describes a portfolio that never existed. CAGR describes yours: 10,000 × 1.0395 = 12,110.
Why the average is always too high
Returns compound by multiplication, not addition. A 25% loss takes $14,040 down to $10,530, and the next year’s 15% gain is earned on that smaller base. The arithmetic mean treats each percentage as if it applied to the same starting amount, so it gives losses too little weight. Mathematically, the geometric mean can never exceed the arithmetic mean (the AM–GM inequality), and the gap widens as returns become more volatile.
The volatility drag shortcut
CAGR ≈ Average return − (Standard deviation² ÷ 2)In the example, the yearly returns have a standard deviation of about 20.3%. So CAGR ≈ 6.00% − (0.203² ÷ 2) ≈ 3.93% — very close to the exact 3.90%. This “volatility drag” is why two funds with the same average return can leave you with very different amounts: the steadier one compounds to more.
Same average, different outcomes
| Two-year path | Average | CAGR | $10,000 becomes |
|---|---|---|---|
| 0%, 0% | 0% | 0.00% | $10,000 |
| +40%, −40% | 0% | −8.35% | $8,400 |
| +50%, −50% | 0% | −13.40% | $7,500 |
Which number to use
- To measure what happened to your money: CAGR. It is the figure fund fact sheets label “annualised return”.
- To compare investments over different periods: CAGR, ideally over the same dates.
- To estimate next year’s expected return in a statistical model: the arithmetic average has a role there — but not as a growth rate.
- When money was added along the way: neither — use XIRR.
Paste a series of yearly values into the Yearly data tab of the CAGR calculator to see both numbers, plus best and worst years and volatility, side by side. For stocks, thestock CAGR calculator explains how dividends change the picture.
Sources and further reading
- Wikipedia: Geometric mean — and the AM–GM inequality
- Wikipedia: Volatility tax — why variance lowers compound growth
- Investor.gov (U.S. SEC): Mutual fund fees and expenses — reading fund performance figures
Educational information only — not investment advice. Past performance does not guarantee future results.
Related questions
Why is CAGR lower than the average annual return?
Because losses hurt more than equal gains help: after a 50% fall you need a 100% gain to break even. The arithmetic average ignores this; CAGR, the geometric mean, includes it. The more returns vary, the bigger the gap.
Can CAGR ever be higher than the average return?
No. The geometric mean is always less than or equal to the arithmetic mean. They are equal only when every year’s return is exactly the same.
Which should I use to compare mutual funds?
CAGR (often labelled “annualised return”). It reflects what actually happened to money left in the fund. The average annual return is useful only as an input to statistical models, not as a measure of growth.
More CAGR guides
- How to calculate CAGRThe formula step by step, by hand, with partial years, losses and revenue.
- What is a good CAGR?Benchmarks from 98 years of stock, bond, gold and cash returns.
- CAGR vs IRR vs XIRRWhich return measure to use when money goes in and out.
- CAGR vs absolute returnTotal gain versus yearly pace — and when to quote each.
- Rule of 72 and doubling timeHow long money takes to double at a given CAGR.
More growth calculators
- CAGR calculatorGrowth rate from start value, end value and time.
- Reverse CAGR calculatorFuture value, starting amount or time needed.
- Stock CAGR calculatorAnnualized returns for shares, with dividends.
- Bitcoin CAGR calculatorBitcoin growth between any two dates.
- CAGR in ExcelFormulas, RRI and a free template.