What-If methodology
Every What-If projection is a deterministic calculation from inputs you set — never a recommendation. This page documents the default assumptions and the engine logic so the numbers are auditable.
Default assumptions
Defaults are deliberately conservative and illustrative — a defensible real return beats an optimistic nominal one. They are editable on every scenario page; change them and the projection recomputes.
| Assumption | Default | Basis |
|---|---|---|
| Nominal annual return | 7% | A conservative long-run diversified-equity assumption, below many historical averages. |
| Inflation | 2.5% | Around typical central-bank inflation targets for developed markets. |
| Real return | ≈4.4% | Derived via the Fisher relation: (1 + nominal) ÷ (1 + inflation) − 1. |
How the projection is calculated
- Compounding: contributions are compounded monthly at the nominal return; the future value is the standard annuity formula.
- Lump sum: a single amount grows at the nominal return over the horizon.
- Today's dollars: every nominal figure is discounted by inflation for each year, so the inflation-adjusted value sits next to it. We never show nominal alone.
- Debt paydown: a straight amortization — extra payments reduce the balance faster; interest saved is the difference between the two payoff paths.
What these projections are not
They are not predictions, forecasts, or recommendations. Real markets vary year to year; a fixed-rate projection is a simplification for comparison, not a claim about the future. Speculative scenarios are framed as pure conditionals ("if X were $Y"), never as predictions. Nothing here is personalized financial advice.
Educational tools only — not financial advice. Assumptions are illustrative and editable.
