Cost drag / fees (Kostenquote)
Cost drag is the portion of investment returns lost to fees — every percentage point charged in costs comes out of performance before the rest compounds. The German term Kostenquote (cost ratio) names the same idea: total costs expressed as a percentage of assets per year. Because fees recur annually, small rate differences accumulate into large differences in final wealth.
Why it matters
Every depot (brokerage account) and every fund carries some layer of cost — broker commissions, fund expense ratios, spreads — and each layer subtracts directly from the return an investor actually keeps. Percentages and shares (percentage basics) explain how to read a cost quoted as a rate; compound interest explains why a recurring annual deduction produces an outsized effect over a multi-decade horizon rather than a proportional one. Treating cost drag as a mechanism, not a fixed number, is the groundwork for evaluating any specific fee metric used to compare investment products.
Worked examples
1. Annual fee in euros. A depot holding €20,000 in a fund with an illustrative annual cost of 0.20% pays about 0.20% x €20,000 = €40 per year in fees. The same €20,000 in a fund charging an illustrative 1.50% pays 1.50% x €20,000 = €300 per year — 7.5 times more, for holding the identical euro amount.
| Fee rate (illustrative) | Annual cost on €20,000 |
|---|---|
| 0.20% | €40 |
| 0.75% | €150 |
| 1.50% | €300 |
2. Compounding over decades. Fees don't only cost money each year — they shrink the base that compounds afterward. Starting from €10,000 growing at an illustrative 7% gross annual return for 30 years: at a 0.20% annual cost (net return 6.80%), the balance reaches about €71,970. At a 1.50% annual cost (net return 5.50%), it reaches about €49,840. A 1.3-percentage-point difference in fees produces a gap of roughly €22,000 — about 31% less final wealth — purely from the fee being deducted before each year's growth compounds on itself.
3. A monthly savings plan at three fee levels. Fees bite hardest on a plan funded month after month. Paying in an illustrative €250/month for 20 years at an illustrative 6% gross annual return, the only thing that changes below is the annual cost: 0.2 percentage points (a cheap index fund), 0.5 p.p. (a pricier index fund), and 1.5 p.p. (a typical fund-in-a-wrapper product).
| Annual cost | Net return | Value after 20 years | vs. cheapest |
|---|---|---|---|
| 0.2 p.p. | 5.8%/year | ~€112,800 | — |
| 0.5 p.p. | 5.5%/year | ~€108,900 | −€3,900 |
| 1.5 p.p. | 4.5%/year | ~€97,000 | −€15,800 |
All three savers pay in the same €60,000 over the 20 years. The 1.3-percentage-point gap between the cheapest and most expensive option costs about €15,800 — more than a quarter of everything contributed — without buying anything extra. The wrapper's higher fee doesn't have to deliver worse investments to lose money; charging more on the same gross return is enough.
Check yourself
A depot (brokerage account) holds €15,000 in a fund with an annual cost of 0.40%. How many euros does that cost in fees for one year?
A fund returns an illustrative 8% gross per year and charges an annual fee of 1.2%. What net annual return do investors actually receive, in percent?
Two funds track the same index. Fund A charges 0.20% per year; Fund B charges 1.20% per year — exactly 1.00 percentage point more. Over a 30-year holding period, how does the euro effect of that 1.00-percentage-point difference compare to its effect in year one?
Which of the following are true about cost drag from fees? (Select all that apply.)