If you have ever looked at a mutual fund factsheet or a comparison page, you have seen these terms — CAGR, Sharpe Ratio, Sortino Ratio, Standard Deviation. Most investors either ignore them or glance past them without truly understanding what they mean or how to use them.
That is a mistake. These four numbers, read together, tell a far more complete story than any headline return figure. A fund with 22% CAGR and a Sharpe ratio of 0.4 is a very different animal from a fund with 18% CAGR and a Sharpe ratio of 1.3. Understanding the difference can save you from investing in funds that look great on paper but feel terrible to actually live through.
01. What is CAGR — and Why It Can Mislead
CAGR stands for Compounded Annual Growth Rate. It answers one question: "If my investment grew from ₹X to ₹Y over N years, what steady annual return rate would explain that growth?"
Example: ₹1 lakh grows to ₹2.19 lakh in 5 years
CAGR = (2.19 ÷ 1) ^ (1 ÷ 5) − 1 = 17% per year
CAGR smooths out all the year-to-year volatility into one clean number. A fund that returned +45%, −30%, +28%, −5%, +22% over five years would still show a single CAGR figure — and that single figure hides everything that happened in between.
The Problem With CAGR Alone
Consider two funds over 5 years, both showing 17% CAGR:
| Year | Fund A — Steady | Fund B — Volatile |
|---|---|---|
| Year 1 | +18% | +62% |
| Year 2 | +14% | −38% |
| Year 3 | +20% | +55% |
| Year 4 | +16% | −22% |
| Year 5 | +19% | +48% |
| 5Y CAGR | 17% | 17% |
| Worst single year | −14% | −38% |
Same CAGR. Completely different experience. An investor in Fund B who saw −38% in Year 2 likely panicked and sold — locking in a loss and never earning the recovery. CAGR tells you the destination. It does not tell you how rough the journey was.
Point-to-point CAGR figures on fund websites are calculated from one fixed date to another — often chosen to show the fund in the best light. A fund's "5-year CAGR" changes dramatically based on the start and end dates chosen. Always combine CAGR with Standard Deviation, Sharpe Ratio, and Rolling Returns for a complete picture.
02. What is Standard Deviation
If CAGR tells you how much a fund returned, Standard Deviation tells you how consistently it got there. It measures how much a fund's monthly returns fluctuate around its average return.
High SD → Returns are all over the place → High volatility → Unpredictable
Low SD → Returns are consistent → Low volatility → More predictable
A Real-World Analogy
Imagine two delivery services. Both deliver in "3 days on average." Service A delivers in 2, 3, 3, 4, 3 days — consistent, predictable. Service B delivers in 1, 7, 2, 1, 4 days — the average is 3 but the experience is chaotic.
Standard deviation measures that chaos. A mutual fund with low standard deviation is like Service A — you know roughly what to expect month to month. A fund with high standard deviation is like Service B — the average return may look fine but the ride is unpredictable.
How to Read Standard Deviation in Indian Mutual Funds
| Category | Typical 3Y Std Dev Range | What It Means |
|---|---|---|
| Large Cap / Index Funds | 12% – 16% | Lower volatility, more predictable |
| Flexi Cap / BAF | 13% – 18% | Moderate volatility |
| Mid Cap Funds | 17% – 23% | Higher volatility, bigger swings |
| Small Cap Funds | 20% – 28% | Highest volatility, most unpredictable |
When comparing two funds in the same category, the one with lower standard deviation and similar returns is the better choice — it delivered similar gains with less turbulence. A small cap fund with 15% standard deviation and 18% CAGR is exceptional. The same numbers in a large cap fund would be ordinary.
Standard Deviation is the foundation for both Sharpe Ratio and Sortino Ratio. Once you understand SD, the next two metrics become much easier to grasp.
03. What is Sharpe Ratio
Sharpe Ratio answers the most important question in investing: "Am I being rewarded enough for the risk I am taking?"
Developed by Nobel laureate William Sharpe, it compares the extra return a fund earns above a risk-free investment (like a government bond) against the volatility (standard deviation) it took to earn that extra return.
In India, the Risk-Free Rate used is typically 6.5% (approximate 10-year G-Sec yield)
Example: Fund return = 18%, Risk-free = 6.5%, Std Dev = 14%
Sharpe = (18 − 6.5) ÷ 14 = 11.5 ÷ 14 = 0.82
How to Interpret the Sharpe Ratio Number
A Tale of Two Funds
| Metric | Fund A | Fund B |
|---|---|---|
| 3Y CAGR | 22% | 17% |
| Standard Deviation | 26% | 14% |
| Risk-Free Rate | 6.5% | 6.5% |
| Sharpe Ratio | 0.60 — Poor | 0.75 — Better |
| Verdict | Higher return but took excessive risk to get there | Lower return but far better risk-adjusted result |
Fund A's 22% CAGR looks better on the surface. But it took enormous volatility (26% standard deviation) to get there — meaning some years it crashed hard. Fund B delivered 17% with far less turbulence. For most investors, Fund B is the better choice — especially those who might panic and sell during a bad year.
Always compare Sharpe ratios within the same category. A small cap fund's Sharpe of 0.7 and a large cap fund's Sharpe of 0.7 are not directly comparable — small cap funds inherently have higher standard deviation. The Sharpe ratio is most useful when comparing Fund A vs Fund B in the same category.
04. What is Sortino Ratio — and Why It is Better Than Sharpe
Sortino Ratio is a smarter version of the Sharpe Ratio. It fixes one important flaw in the Sharpe calculation.
The Sharpe Ratio penalises a fund for all volatility — both upside and downside. But think about that for a moment. If your fund shoots up 40% in a great month, that is volatility — but it is good volatility. Why penalise a fund for going up sharply?
The Sortino Ratio only counts downside volatility — the bad kind of fluctuation. Returns above the target (usually the risk-free rate) are ignored. Only the months where the fund fell below the target are counted as "risk."
Where Downside Deviation = Standard deviation of only the negative/below-target return months
Example: Fund return = 18%, Target = 6.5%, Downside Deviation = 9%
Sortino = (18 − 6.5) ÷ 9 = 11.5 ÷ 9 = 1.28
Sharpe vs Sortino — Which Should You Use?
| Aspect | Sharpe Ratio | Sortino Ratio |
|---|---|---|
| What risk it measures | Total volatility — both up and down | Only downside volatility — the bad kind |
| Penalises upside volatility? | Yes — a fund that shoots up gets penalised | No — only counts downside as risk |
| Best used for | Quick, general comparison between funds | More accurate risk assessment for equity funds |
| Which is more investor-friendly? | Less — ignores the difference between good and bad volatility | More — aligns with how investors actually experience risk |
| Limitation | Can unfairly penalise funds with strong upside momentum | Less standardised — fewer fund factsheets report it |
Use Sharpe Ratio for a quick, industry-standard comparison between funds. Use Sortino Ratio when you want a more accurate picture of how a fund handles the bad months specifically. A fund with a high Sortino but mediocre Sharpe is a fund that soars when markets rise but protects well when markets fall — exactly what most investors want.
How to Read Sortino Ratio for Indian Equity Funds
05. How to Use All Four Together
No single number tells the complete story. The real skill is reading all four together — CAGR, Standard Deviation, Sharpe Ratio and Sortino Ratio — as a set. Here is how they work together in practice.
Step-by-Step Fund Evaluation Framework
Look at the 3-year and 5-year CAGR. This sets the baseline. But do not stop here. A fund with 24% CAGR may look brilliant until you see the next numbers.
How much did it swing to achieve that CAGR? Compare to the category average. If the fund's standard deviation is significantly higher than peers, the CAGR came at a cost — the cost of extreme volatility most investors could not stay through.
Now you can compare risk-adjusted returns. The fund with the higher Sharpe ratio earned more return per unit of risk. This is the most important comparison when choosing between two funds in the same category.
A high Sortino ratio confirms the fund manages bad months well — it does not just earn high returns by riding bull markets recklessly. A fund with high Sharpe AND high Sortino is a genuinely well-managed fund.
These four ratios complement — not replace — Drawdown and Rolling Returns. Maximum Drawdown tells you the worst loss in the fund's history. Rolling Returns tell you how consistent performance has been across all market phases. Together, all six metrics give you a complete picture.
06. Benchmarks — What Numbers Are Good?
Here is a quick reference for evaluating Indian equity mutual funds across all four metrics. These are approximate ranges based on historical data — individual funds will vary.
| Metric | Poor | Acceptable | Good | Excellent |
|---|---|---|---|---|
| CAGR (5Y) | Below 10% | 10% – 14% | 14% – 18% | Above 18% |
| Std Dev (3Y) Lower is better |
Above 25% | 20% – 25% | 14% – 20% | Below 14% |
| Sharpe Ratio (3Y) | Below 0.5 | 0.5 – 1.0 | 1.0 – 1.5 | Above 1.5 |
| Sortino Ratio (3Y) | Below 0.8 | 0.8 – 1.2 | 1.2 – 1.8 | Above 1.8 |
A small cap fund with a Sharpe of 0.8 may be excellent for its category. A large cap fund with a Sharpe of 0.8 may be average. These benchmarks are general guides — always compare a fund against its category peers, not across different categories. Standard deviation benchmarks especially vary widely by category.
07. Quick Reference Checklist
1. 5Y CAGR — The baseline return. Do not rely on this alone.
2. 3Y Standard Deviation — How volatile was the journey? Compare to category average.
3. 3Y Sharpe Ratio — Was the return worth the total risk taken? Higher is better within category.
4. 3Y Sortino Ratio — Was the return worth the downside risk specifically? Higher is better.
5. Maximum Drawdown — The worst fall in the fund's history. Can you handle that number in rupees? Learn more →
6. Rolling Returns — Is the CAGR consistent, or was it a lucky period? Learn more →
All six of these metrics are shown on every fund comparison page on RightAdvise — calculated from daily NAV data pulled directly from our database. No estimates, no marketing numbers.
See These Metrics In Real Funds
Every RightAdvise category page shows live Sharpe ratio, Standard Deviation, Max Drawdown and 5Y CAGR for India's top funds — calculated from daily NAV data. See the real numbers: