Backtests and fund factsheets throw around total return and CAGR (compound annual growth rate). They answer related questions but are not interchangeable.
Total return
Total return is the overall percent change from start value to end value over the full window, including reinvested gains:
total return = (ending value / starting value) - 1
Example: $100k grows to $161k over five years.
total return = 61%
Total return is honest about the period you chose. It says nothing about whether growth was smooth or back-loaded.
CAGR
CAGR is the constant yearly growth rate that would compound from start to end:
CAGR = (ending value / starting value)^(1 / years) - 1
Same example: $100k to $161k in five years.
CAGR ≈ (1.61)^(1/5) - 1 ≈ 10% per year
CAGR is a summary annualized rate assuming steady compounding, which real paths rarely follow.
Side-by-side
| Total return | CAGR | |
|---|---|---|
| Question answered | How much did I make over the whole span? | What yearly rate compounds to that outcome? |
| Depends on length | Yes - longer windows can show larger totals | Normalizes to per-year |
| Path ignored | Yes | Yes |
Two strategies with identical CAGR can feel very different if one drew down 40% mid-period (max drawdown).
Common mistakes
- Comparing total returns across different lengths - 80% over 10 years vs 80% over 3 years.
- Treating CAGR as promised future growth - it is historical summary only.
- Ignoring contributions and withdrawals - personal cash flows need IRR-style measures, not simple CAGR on a lump sum.
- Short windows - One great year produces heroic CAGR that is not repeatable.
With volatility and risk metrics
High CAGR with extreme volatility or shallow Calmar tells a fuller story than CAGR alone.
When evaluating rules-based strategies, state start and end dates explicitly (how to choose a backtest start date).
Practical habit
Report both total return and CAGR for the same window, plus drawdown and Sharpe. Readers can then judge magnitude, annualized pace, and risk in one glance.
