The assumptions, out loud
The calculator trims the advertised rate by a scenario-based haircut: 0.7 points in Fair skies (top-quartile platform, no defaults touch your slice), 2.4 points in Most likely (a normal year of defaults, partial recoveries and cash waiting between loans), and 5.7 points in Rough year (elevated defaults, slow recoveries). These trims are calibrated to the documented gap between advertised and realised returns across European platforms.
"Reinvest" compounds monthly; "Pay out" sends interest to your account and keeps principal flat. The ETF benchmark assumes a broad index fund at 7% nominal - the long-run average, minus the volatility a single line cannot show. The deposit line uses 2.5% with state guarantees up to EUR 100,000. Taxes are not modelled - see the tax guide. None of this is investment advice: it is arithmetic with honest inputs.