The debate between active and passive investing has been settled by data. Yet billions of euros continue to flow into expensive active funds that, on average, deliver worse results than low-cost index funds. Understanding why helps you make smarter decisions with your money.
What Is an Index Fund?
An index fund is an investment fund that tracks a market index — like the S&P 500, MSCI World, or STOXX Europe 600 — by holding the same securities in the same proportions. It does not attempt to outperform the market; it aims to match it. Because there is no active management, fees are extremely low.
What Is an Active Fund?
An actively managed fund employs professional fund managers and analysts who research securities and make decisions about what to buy and sell, with the goal of outperforming a benchmark index. These services cost money — annual fees of 1–2% are typical, plus transaction costs.
The Evidence Is Clear
The S&P SPIVA (S&P Indices Versus Active) report is the most comprehensive ongoing study of active fund performance. Key findings over 15-year periods consistently show:
- ~85-90% of actively managed US equity funds underperform the S&P 500
- ~80-85% of European equity funds underperform their respective benchmarks
- Performance only worsens over longer time horizons
- Past outperformance is not predictive of future outperformance
Vanguard founder John Bogle spent his career studying this. His conclusion: in aggregate, before costs, active managers match the market (they are the market). After costs, they systematically underperform.
Why Active Funds Struggle to Beat the Market
The Cost Disadvantage
An index ETF charging 0.07% per year starts each year just 0.07% behind the market. An active fund charging 1.5% must outperform the market by 1.5% just to break even. Consistently doing this over decades is extraordinarily difficult.
Market Efficiency
Modern markets incorporate information rapidly. When thousands of sophisticated analysts all scrutinize the same companies using vast data resources, prices quickly reflect known information. Finding genuinely mispriced securities is extremely difficult and getting harder as markets become more informationally efficient.
The Zero-Sum Game
For every active manager who outperforms the index, another must underperform by the same amount. After costs are taken out of this zero-sum game, the average active investor necessarily underperforms the market average.
Survivorship Bias
Underperforming funds are quietly closed or merged, making the historical record of active funds look better than it actually is. Studies accounting for this bias find even worse performance from active managers.
When Might Active Management Be Worth It?
There are some niche cases where active management may add value:
- Illiquid or inefficient markets — some emerging market segments, small-cap stocks, or private credit markets may have less information efficiency
- Specific alternative strategies — certain absolute return or market-neutral strategies don’t aim to beat a stock benchmark at all
- Tax-managed strategies — some active approaches can optimize tax outcomes in specific jurisdictions
Even in these cases, the bar is high and the evidence thin. The burden of proof lies with the active manager, not the passive investor.
The Cost Difference Illustrated
Assume €100,000 invested over 30 years, earning 7% gross returns:
- Index fund (0.1% fee): final value ≈ €739,000
- Active fund (1.5% fee): final value ≈ €551,000
The fee difference costs you €188,000 — nearly twice your original investment — over 30 years. And that assumes the active fund matches the index gross of fees, which most do not.
Building a Portfolio with Index Funds
A simple, proven approach:
- Choose a globally diversified equity index ETF (MSCI World or MSCI ACWI)
- Add a bond index ETF proportional to your risk tolerance and time horizon
- Invest regularly, regardless of market conditions
- Rebalance annually to maintain your target allocation
- Never try to time the market or switch to the “hot” fund of the year
This approach — boring as it may sound — has consistently outperformed most professional investors and delivers outcomes that compound to substantial wealth over a working lifetime.