XIRR vs CAGR vs AUM: Mutual Fund Metrics Every Investor Must Understand
Two investors discuss their SIP returns over coffee. One says her fund "gave 14.2% returns" since 2019. The other says his fund "delivered 22%" in the same period. They both invested in the same large-cap fund. The difference: she's quoting XIRR. He's quoting point-to-point CAGR. Both are correct. Only one is useful for her decision. Mutual fund metrics get used loosely in Indian retail conversation, and the imprecision costs people money. CAGR, XIRR, and AUM all sound like return numbers, but they answer completely different questions. Here's the working investor's guide to all three — what each measures, when to use it, and the traps that come from using the wrong one.
Metric | What It Measures | Use For | Watch Out For |
CAGR | The annualized growth rate of a single lump-sum investment over a period | Comparing fund returns over fixed windows | Doesn't account for SIPs or staggered investments |
XIRR | The annualized return when cash flows happen on different dates | SIP investors, anyone with multiple investments + withdrawals | Sensitive to the exact dates; small changes can shift the number |
AUM | Total assets under the fund's management | Gauging fund popularity + liquidity health | Not a return metric — large AUM doesn't mean better returns |
Common confusion | Using CAGR for SIP returns | Always use XIRR for SIPs | CAGR overstates SIP returns by 1.5–2× usually |
2026 reality | Most SIP investors quote CAGR by mistake | XIRR is what matters for their actual experience | AMFI shows both — pick the right one |
CAGR — Compound Annual Growth Rate
Definition. The constant annual rate at which a single lump-sum investment would have to grow to reach its end value over a specified period.
Formula. CAGR = (End Value / Start Value)^(1/years) − 1
Worked example. You invested ₹1,00,000 in a fund on 1 January 2020. On 1 January 2026,it is worth ₹2,11,358. The period is 6 years.
CAGR = (2,11,358 / 1,00,000)^(1/6) − 1 = (2.11358)^(0.1667) − 1 = 0.1335 = 13.35%
So your fund delivered a 13.35% CAGR over those 6 years.
Where CAGR works perfectly. A one-time investment held untouched for a defined period. The numerator and denominator are both single, unambiguous values. CAGR cleanly summarizes the experience.
Where CAGR breaks. SIP investing. If you invested ₹10,000 every month for 6 years (72 SIP installments, total ₹7.2 lakh invested), the simple CAGR formula doesn't work — your purchases happened at different NAVs on different dates. The "start value" is ambiguous. The "duration" is averaging multiple different holding periods. Using CAGR here is wrong, and the number it produces is misleadingly optimistic.
XIRR — Extended Internal Rate of Return
Definition. The single annualized rate of return that makes the net present value of all cash flows (investments + withdrawals + final value) equal to zero. It handles cash flows happening on different dates.
Formula. There is no closed-form formula — XIRR is computed iteratively. Excel and Google Sheets have an XIRR() function. Manual calculation requires Newton-Raphson iteration or a Spreadsheet.
Worked example. You SIP'd ₹10,000 on the 1st of every month from January 2020 to December 2025. On 31 December 2025, your fund value is ₹11.50 lakh. You contributed ₹7.2 lakh over 72 installments.
Inputs to Excel XIRR: 72 outflows of ₹10,000 each on the 1st of each month, plus one inflow of ₹11,50,000 on 31 Dec 2025
XIRR = approximately 16.8% (the rate that makes the NPV of all those cash flows = 0)
So your SIP "experience" was 16.8% XIRR — meaningfully different from the same fund's CAGR over the period (which might be 13.35% per the earlier example).
Why XIRR > CAGR for the same fund and period. Each SIP installment had a shorter exposure than the original lump-sum. Money you invested in 2024 was only at risk for 1–2 years before the period ended; money you invested in 2020 had 6 years. The weighted average exposure is much less than 6 years. XIRR accounts for this weighting. CAGR doesn't.
Why XIRR < CAGR is also possible. If markets crashed near the end of the period, your most recent SIPs went in at higher NAVs and now sit on losses. XIRR captures that pain. CAGR (computed on the fund's own NAV over the period) wouldn't.
When to Use Which
Investing Pattern | Right Metric |
One-time lump sum, held untouched | CAGR |
SIP every month, no withdrawals | XIRR |
Lump sum + occasional top-ups | XIRR |
SIP + partial withdrawals | XIRR |
Two-asset comparison over a fixed period | CAGR (apples to apples) |
Comparing two SIP portfolios | XIRR (only meaningful number) |
The single rule that catches 90% of investor confusion: if you have more than one cash flow date, use XIRR. Always.
AUM — Assets Under Management
Definition. The total value of all investors' holdings in the fund, summed up. If the fund has 5,00,000 units outstanding at NAV ₹150, AUM is ₹7.5 crore. AUM grows when investors invest into the fund and when the NAV appreciates. It shrinks when investors redeem and when NAV falls.
Why AUM matters.
1. Liquidity. A fund with ₹500 crore AUM has more liquid trading in its underlying holdings than a ₹50 crore one. When investors redeem en masse, large AUM funds handle it more smoothly.
2. Cost structure. SEBI's expense ratio caps step down as AUM grows. A ₹500 crore equity fund has a higher max expense ratio than a ₹5,000 crore one. Larger funds are cheaper to investors.
3. Manager attention. Very large funds (₹50,000+ crore) sometimes struggle to deploy capital in small/mid-cap categories without distorting prices. Very small funds (<₹100 crore) may lack institutional rigor.
Why AUM is NOT a return metric. A fund can have ₹50,000 crore AUM and deliver mediocre returns. Investors flock to funds with brand recognition or past star performance, not necessarily future-good performance. Always look at returns and risk metrics separately from AUM.
The AUM Goldilocks zone for equity funds (2026 rule of thumb). Small/mid-cap funds: ₹500 crore – ₹15,000 crore tends to be the executable range. Large-cap funds tolerate much higher AUM (some good ones cross ₹50,000 crore without issue). Skip sub-₹100 crore funds for primary holdings — too small to absorb redemptions without volatility.
Three Other Metrics You Should Know
Beyond CAGR, XIRR, and AUM, three more numbers appear constantly:
1. Standard deviation (σ). Measures volatility — how much the fund's monthly returns deviate from its average return. Higher σ = bumpier ride. Reported on AMFI scheme info as "Risk Grade." Use for comparing funds within the same category.
2. Sharpe ratio. (Return − Risk-free rate) / Standard deviation. Measures return per unit of risk. Higher is better. A Sharpe of 1.0+ over a 3+ year window is generally good for equity; 0.5 is average; below 0.3 is poor.
3. Expense ratio. Annual cost of the fund as a % of AUM, deducted daily from NAV. SEBI caps vary by AUM tier. As of 2026, equity scheme expense ratios range from 0.5–2.25% (direct) and 0.8–2.5% (regular). Lower is generally better — over long periods, a 0.5% difference compounds to lakhs.
Common Indian Investor Mistakes
Mistake 1: Quoting CAGR for SIP returns. "My SIP gave 15% CAGR" — almost certainly wrong. The actual SIP experience is the XIRR, which is usually meaningfully different. Most AMFI factsheets show both; investors often ignore the SIP-specific XIRR column.
Mistake 2: Using AUM as a quality signal. "It must be a great fund — it has ₹40,000 crore AUM." AUM signals popularity and trust at some point in history, not current or future returns. Look at the 3 and 5-year returns vs benchmark and category.
Mistake 3: Comparing CAGR across different start dates. "My fund did 18% CAGR in 5 years; my friend's did 22% in 4 years." Different starting points capture different market regimes. Use rolling returns (CAGR computed over many overlapping windows) for fair Comparison.
Mistake 4: Ignoring XIRR for goal planning. When projecting "how much will my SIP be worth in 10 years," use expected XIRR ranges, not nominal "fund CAGR" numbers. The XIRR is what your actual corpus will reflect.
Mistake 5: Chasing past CAGR. A fund that did 22% CAGR over a 3-year window often did so because of a specific factor tailwind (small-cap rally, value resurgence, IT thematic rally). The same fund usually mean-reverts in the next 2–3 year window. Past CAGR is a backward mirror, not a forward signal.
How to Pull These Metrics for Your Own Funds
For Indian mutual funds, your sources are:
• AMFI factsheets — every AMC publishes monthly factsheets showing NAV, AUM,expense ratio, σ, Sharpe, and 1/3/5/10-year returns. Free download.
• Value Research — independent rating agency. Shows CAGR + rolling returns + SIPXIRR for every fund.
• Morningstar India — similar, often with better risk-adjusted metrics.
• CAMS / KFintech CAS — your personal Consolidated Account Statement shows your individual XIRR per folio (the most relevant number for you specifically).
• Excel XIRR() function — for custom periods or hypothetical scenarios.
Frequently Asked Questions
Q : What's the difference between CAGR and XIRR?
CAGR assumes one start date and one end date with no cash flow in between — it's the constant annual growth rate of a single lump-sum investment. XIRR handles multiple cash flows on different dates, like SIPs or staggered investments + withdrawals. For SIP investors, XIRR is the right metric; CAGR overstates the actual return.
Q : What is a good XIRR for a mutual fund?
For Indian equity mutual funds, a long-term XIRR of 12–15% is good; 15–18% is excellent; above 18% is rare and usually involves elevated risk or favorable timing. Debt funds typically show 6–8% XIRR. Hybrid funds fall between, 9–12%.
Q : How is AUM calculated?
AUM = number of outstanding units × NAV. As investors invest into or redeem from the fund, the unit count changes; as the NAV moves, the per-unit value changes. AUM reflects both flows and performance.
Q : Why does my SIP show a different XIRR than the fund's CAGR?
CAGR is the fund's NAV-based growth over a period — a single number. Your SIP XIRR depends on the specific dates and amounts of your installments. Two investors in the same fund over the same broad period will have different XIRRs based on their individual cash flow timing.
Q : What's a good expense ratio for an equity mutual fund?
For direct plans, look for 0.5–1.0% for actively managed equity funds and 0.1–0.4% for index funds. Regular plans run 0.5–1.0% higher than direct. Over 20+ years, a 0.5% expense ratio difference can mean a 10–12% difference in final corpus due to compounding.
Q : Is high AUM a problem?
For small-cap and mid-cap funds, very high AUM (above ₹15,000 crore for small-caps) can constrain manager flexibility — the fund may struggle to enter or exit positions without moving prices. For large-cap funds, very high AUM is rarely a problem.
Q : How do I calculate XIRR myself?
Use Excel or Google Sheets. List every cash flow with its date — outflows (investments) as negative numbers, inflows (withdrawals + final corpus value) as positive. Apply =XIRR(values, dates) to the two columns. The function returns the annualized rate.
Q : Does the fund's past CAGR predict future returns?
Weakly at best. Past 1-year CAGR has near-zero predictive power for the next year. 5-year and 10-year CAGR have slightly better persistence but still subject to mean reversion. Manager continuity, mandate clarity, expense ratio, and category fundamentals tend to be more predictive than past-period CAGR.