No one volunteers to ask what their money would have become if they'd decided differently. It's an uncomfortable question. It's also the only one that really calibrates future decisions. This calculator asks it cleanly, no blame, no recommendation, just numbers.
What you see
You enter an amount and a time period. We show what that amount would have become in each of the major asset classes: cash under the mattress (i.e. inflation-deflated using Destatis's CPI), average overnight savings (Bundesbank data on mean Tagesgeld rates), the German residential property index (Destatis), gold and silver (Bundesbank), and the major indices: MSCI World, DAX, S&P 500, FTSE 100. Every line is real; every source is linked.
What the data shows
Three observations that hold up over almost any sufficiently long window:
Cash loses. Over any period longer than five years since 2000, holding pure cash has lost in real terms, not in steps, but steadily. The loss is invisible, because the nominal figure on the account stays the same. In real terms, it's one of the most expensive choices available.
Tagesgeld sits just above the waterline, often below. Through the zero-rate years of 2014–2022, the average overnight rate was below inflation. Real terms: a losing investment. Today, with rates at 1.3% and inflation at 2.9%: still real-negative.
Broadly diversified equities win, with bumps. The MSCI World has returned about 5–6% per year in real EUR terms since 2000. That includes the dot-com crash, the 2008 financial crisis, the 2020 COVID shock, and the 2022 inflation drawdown. The volatility is real; the trend is unambiguous.
What this calculator isn't
Not investment advice. Not a forecast. Past data has the well-known cosmetic flaw that the future will look different, we just don't know how. What past data does well: it calibrates expectations. Anyone who thinks their savings account is "safe" can see what's actually happened. Anyone fearful of equities can see whether the volatility historically justified the return.
Capital gains tax (Abgeltungssteuer at 25% plus Soli plus optional church tax) is not deducted from the comparison values, we compare gross performance because tax circumstances are individual. In a real account, expect 26–28% to come off the capital gain.