Fund fees are quoted in numbers small enough to ignore — 0.07%, 0.32% — and that framing is exactly why they are ignored. A fee is charged on the whole balance every year forever, which means it compounds with the same arithmetic that grows the balance itself. Over thirty years, a fraction of a percent is not a rounding error.
The cleanest way to see it is two ETFs tracking nearly the same world index at very different expense ratios. Below, the comparison drawn out: same exposure, several times the yearly cost, and the widening gap when the fee drag is extended over a long horizon.
Both of these funds hold the whole world in one ETF — developed and emerging markets, thousands of companies, the same Morningstar category (Global Large-Stock Blend). The ETF-Compare page puts them side by side:
$33.1B Fund size | 21.5% Return 3y ann. | 13.0% Volatility 1y |
1.06 Sharpe 3y | 4/5 Morningstar |
$81.2B Fund size | 21.3% Return 3y ann. | 13.0% Volatility 1y |
1.03 Sharpe 3y | 4/5 Morningstar |
Compounded, that sentence becomes a chart. On the Cost tab’s own formula — the fee eating at a static $10,000, no market return assumed — 0.32% a year adds up to $915 of cumulative cost over 30 years, against $208 at 0.07% — a $708 gap on the same exposure:

Growth raises the stakes. Let the same $10,000 compound at a flat, hypothetical 5% a year — identical for both funds, so the only difference is each fund’s fee — and after 30 years the position ends at $43,886 in the cheaper fund versus $40,715 in the pricier one. The same 0.25-point fee difference now costs $3,171 — 4.5× the no-growth gap, because the fee also eats the growth it would have compounded. Put differently: the higher fee consumes 9.2% of the 30-year outcome, the lower one 2.1%:


The same page works for any two or three ETFs Slowio follows — TER, size, returns, volatility and ratings in one table, best and worst highlighted.
Slowio is an educational research tool, not financial advice. Figures are computed from Slowio’s data snapshot at build time and may not reflect the latest market data — nothing in this email is a recommendation to buy or sell any security. Do your own research.
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