Projection & Forecasting Methodology

Projections are hypothetical illustrations — they are not promises about the future.

What a projection is

A projection is a mathematical extrapolation of the inputs and assumptions you provide. Given a starting balance, a contribution schedule and an assumed rate of return, the calculator compounds the inputs forward in time and displays the result.

What a projection is not

A guarantee of future performance.
A personalized forecast of your financial future.
A substitute for advice from a licensed professional.

Why outcomes will differ

Real outcomes diverge from projections because of market volatility, sequence-of-returns risk, inflation surprises, regulatory and tax changes, fees and spreads, changes in personal circumstances, and behavioral choices.

How we present uncertainty

Where relevant, calculators expose toggles for rate of return, inflation and contribution growth so users can run multiple scenarios. We prefer ranges and side-by-side comparisons over single-number forecasts.

Long horizons amplify error

Small differences in assumed returns compound into large differences over decades. A 30-year projection is far more sensitive to assumption changes than a 3-year one. Treat long-horizon outputs as orders of magnitude, not precise dollar figures.

See Assumptions & Limitations and the Market Volatility Statement.

This page is part of the CalculatingWealth.com Wealth Planning Trust Center. For an overview of every policy, methodology and disclosure, visit the Trust Center. Nothing on this page is personalized financial, investment, tax, legal or accounting advice — see the Financial Disclaimer.