How to Evaluate Mutual Fund Performance: CAGR, XIRR, Sharpe, Alpha, and More

Why Returns Alone Are Misleading

The most common mistake retail investors make is comparing two funds purely on 1-year or 3-year returns. A fund that returned 28% last year may have taken twice the risk of one that returned 22%. A fund with a great 3-year return may have had a disastrous 2019 and recovered only because the entire market rebounded. To evaluate a fund properly, you need a toolkit — not a single number.

CAGR: The Starting Point

Compound Annual Growth Rate (CAGR) is the smoothed annualised return on a lump sum investment. If you invested ₹1 lakh in a fund in June 2019 and it became ₹2.1 lakh by June 2024, the 5-year CAGR is:

CAGR = (2,10,000 / 1,00,000)^(1/5) − 1 = (2.1)^0.2 − 1 ≈ 16%

CAGR is clean and comparable across funds. Always use 5-year or 10-year CAGR — never 1-year, which is too short to be meaningful and can be gamed by market timing.

XIRR: The Right Metric for SIPs

CAGR assumes a single lump sum. For SIP investments where you add money monthly, XIRR (Extended Internal Rate of Return) is the correct measure. It accounts for the fact that different instalments have been invested for different time periods.

If your SIP account shows ₹3.6 lakh invested and current value is ₹5.2 lakh, but the investments were spread over 36 months, the CAGR calculation would be wrong. XIRR will give you the actual annualised return on each rupee for the time it was invested. Most mutual fund platforms (Kuvera, Groww, Coin) display XIRR directly. A good equity fund SIP running for 5+ years should show XIRR of 11–15% in normal markets.

Rolling Returns: The Most Honest Test

Point-to-point returns (e.g., 5-year CAGR from January 2019 to January 2024) depend heavily on start and end dates. A fund might look great if you measure from a market bottom. Rolling returns fix this by measuring the return for every possible period of a given length.

For example, for 3-year rolling returns over the last 10 years: calculate the 3-year CAGR starting January 2015, then February 2015, then March 2015 — all the way through. This gives ~84 data points. A fund is consistently good only if the median and minimum rolling return are strong.

Where to find rolling returns: Value Research Online, Morningstar India, and ICICI Direct's fund research section show rolling return charts. A fund with median 3-year rolling return of 14% and minimum of 4% is more reliable than one with median 16% and minimum of -8%.

Benchmark Comparison: The Non-Negotiable Test

Every mutual fund has a benchmark — a relevant index it should beat. A large cap fund's benchmark is typically Nifty 100 TRI (Total Return Index, which includes dividends). A mid cap fund's benchmark is the Nifty Midcap 150 TRI.

Always compare fund returns against the benchmark TRI, not the plain price index. The price index (Nifty 50) ignores dividends; the TRI includes them, making it a harder and fairer benchmark. If a fund's 5-year CAGR is 13% and Nifty 100 TRI returned 12.5%, the outperformance is only 0.5% — likely wiped out by the expense ratio difference vs an index fund.

A fund worth holding should outperform its benchmark TRI by at least 1.5–2% per year on a rolling 5-year basis.

Alpha: Skill After Adjusting for Market

Alpha measures how much return the fund generated above what the market alone would have delivered, given the fund's level of market exposure (beta). A positive alpha means the fund manager added genuine value.

Example: if the market returned 12% and the fund (with beta 0.9) returned 14%, the expected return was 12% × 0.9 = 10.8%. The alpha is 14% − 10.8% = 3.2%. A consistently positive alpha over 3+ years suggests real fund manager skill, not luck.

Alpha below 0 means the manager destroyed value relative to passive investing. Combined with the expense ratio, negative or near-zero alpha is the strongest argument for switching to an index fund.

Sharpe Ratio: Return Per Unit of Risk

Sharpe ratio = (Portfolio Return − Risk-Free Rate) / Standard Deviation of Returns

In India, use the 91-day T-bill yield (~6.5%) as the risk-free rate. If a fund returns 14% with a standard deviation of 16%, its Sharpe ratio is (14 − 6.5) / 16 = 0.47.

Higher Sharpe ratio is better. It tells you how much return you earned per unit of volatility you absorbed. A fund returning 18% but with a Sharpe of 0.4 may be inferior to one returning 14% with a Sharpe of 0.7 — because the second fund delivered more return per unit of risk taken.

Compare Sharpe ratios within the same fund category only — comparing a mid cap fund to a debt fund is meaningless.

A Quick Evaluation Checklist

Before investing in or continuing to hold a mutual fund, check:

1. 5-year rolling CAGR vs benchmark TRI — outperformance of 1.5%+ over most rolling periods
2. XIRR on your actual SIP — should reflect long-term equity expectations
3. Sharpe ratio — higher than category average (Value Research Online shows category averages)
4. Alpha (Jensen's) — consistently positive over 3–5 years
5. Expense ratio (direct plan) — for large cap: under 0.5%; mid/small cap: under 1%
6. Fund manager tenure — returns should persist through the same manager, not a recent change
7. AUM — very small AUM (under ₹200 crore) raises liquidity risk; very large AUM (over ₹30,000 crore for active mid cap) may impair performance due to size constraints

The Takeaways

• CAGR is for lump sum comparison; XIRR is the correct metric for SIP investors — use both.
• Rolling returns over 3–5 year windows are more reliable than point-to-point returns, which depend on start/end dates.
• Always compare against the benchmark Total Return Index (TRI), not the plain price index.
• Alpha above zero over 3+ years indicates genuine fund manager skill; negative alpha is an argument for switching to an index fund.
• Sharpe ratio tells you return per unit of risk — compare within the same fund category.
• Expense ratio, fund manager tenure, and AUM size are qualitative checks that complete the picture.