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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 ↓
§ 01
SPY — S&P 500 Price, Today's Change. Open SPY on the Ledge to see current values.
§ 02
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)
§ 03
Fee Cost = Portfolio × [(1+r−fee_low)ⁿ − (1+r−fee_high)ⁿ]
§ 04

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.

§ 05
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.
§ 06
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?
§ 07

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.

§ 08

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.

§ 09

**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.

Five questions · AI feedback

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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