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L.5 · BEGINNER · 4 MIN

Index Funds: Why Most Active Funds Underperform

S&P's SPIVA Scorecard finds that over 15-year windows, roughly 85-90% of actively managed US large-cap funds underperform their benchmark net of fees. The figure varies by category (small-cap, international) and time period. Index investing - buying the entire market at near-zero cost - was popularized by Bogle (Vanguard founder, 1976) and publicly endorsed for most retail investors by Buffett (Berkshire Hathaway 2013 letter).

Quiz · 5 questions ↓

Live S&P 500 ETF (SPY) price and daily move

SPY — S&P 500 (SPY), Today's Change. Open SPY on the Ledge to see current values.

Index funds versus active funds, feature by feature

FeatureIndex FundActive Fund
Expense ratio0.03–0.10%0.50–1.50%
TurnoverLow (3–5% annually)High (50–100%+)
Tax efficiencyHigh (few taxable events)Low (frequent trading creates taxes)
Manager riskNone — follows the indexStar manager leaves, style drifts
15-year odds of matching the indexVery high — tracks index by construction, net of a tiny expense ratio (0.03–0.10%) and minimal tracking error~10–15% (US large-cap, net of fees; source: SPIVA Scorecard 2008–2023 15-year window; lower for international equity and small-cap categories)

How fund fees compound against you

Fee Cost = Portfolio × [(1+r−fee_low)ⁿ − (1+r−fee_high)ⁿ]

What a 1 percent fee costs over 30 years

On a $100K portfolio over 30 years at 10% gross return, the difference between a 0.05% index fund and a 1.0% active fund is approximately $395,000 over 30 years. Fees compound against you just like returns compound for you.

Check the expense ratio you are paying

Check the expense ratio of your current investments. If you’re paying more than 0.20%, calculate how much those fees cost you over 30 years using the calculator above.

Whether a three-year winning streak proves skill

A financial advisor recommends an actively managed fund with a 1.2% expense ratio that has beaten the S&P 500 for the last 3 years. Should you invest?

The simple three-fund portfolio

The three-fund portfolio (total US stock market + total international + total bond market) with index funds gives you global diversification, near-zero fees, and historically better returns than most professional managers. Simplicity wins.

How the underperformance figures vary by category

Data note: SPIVA underperformance figures

The ~85–90% underperformance figure cited in this module applies specifically to US large-cap active funds over 15-year windows (SPIVA US Scorecard, S&P Global, 2008–2023 data). Underperformance rates differ by category and period: international equity funds underperform at roughly 80–85%; small-cap and emerging-markets active funds show a wider range (60–90%) and can outperform over shorter windows. The index fund column of the table above shows 'very high odds of matching the index' — not 'guaranteed to beat active funds' — because 'matching the index by construction' and 'active funds underperforming' are two different propositions. Verify the most current SPIVA data at spglobal.com/spiva before citing any specific percentage.

Where active funds can win, plus values and factor tilts

When active management does win — and a vocabulary note on ESG and factor tilts

Where active has a credible edge: The indexing case is strongest in US large-cap equities — the most analyzed, most liquid, most efficiently priced market in the world. SPIVA data shows active underperformance is materially lower (i.e., active managers do relatively better) in less-efficient corners: international developed equity (~80-85% underperform over 15 years), small-cap US (~70%), and emerging markets (~60-90% depending on window). Credit markets (high-yield bonds, CLOs) also show more active-manager persistence than large-cap equity. The conclusion is not 'active never wins' — it is that the US large-cap index is where the case for passive is overwhelming, and where most retail money lives.

ESG screens: ESG (Environmental, Social, Governance) funds apply non-financial filters to exclude or tilt away from companies that score poorly on environmental footprint, labor practices, or board quality. ESG funds are often index-like in structure but with the screened universe. Academic evidence on whether ESG screens improve or impair returns is mixed. Oxford Ledge neither recommends nor discourages ESG investing; it is a values-plus-return framework the learner should understand.

Factor tilts (a vocabulary entry): Academic research (Fama-French, Carhart) identifies four return factors that have historically produced excess returns over the broad market — though persistence is debated: (1) Size — small-cap stocks have historically outperformed large-cap over long horizons; (2) Value — stocks cheap relative to book value or earnings have historically outperformed growth stocks; (3) Profitability — more profitable firms outperform less profitable; (4) Momentum — stocks that have recently risen tend to continue rising over the next 3-12 months. Factor-tilt funds (sometimes called 'smart beta') attempt to systematically capture these premiums at index-fund cost levels. Whether the premiums persist after publication and widespread adoption is an open empirical question.

Check your understanding

Sit with the ideas.

Buffett's $1M bet (2008-2017): a Vanguard S&P 500 index fund returned 125.8% while a portfolio of hedge funds returned 36%. What does this primarily demonstrate?

Why:
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