Build Back Better Calculator — Financial Recovery Planner

Formula

How this is calculated

This calculator models a financial recovery as a compound future-value problem. Starting from your current balance C, you add a fixed monthly contribution M each month, and the combined balance compounds at a monthly rate r/12. The formula Balance(n) = C × (1 + r/12)ⁿ + M × [(1 + r/12)ⁿ − 1] / (r/12) gives the projected balance after n months, and the calculator finds the first month n at which this balance reaches or exceeds your target.

The annual return rate reflects the asset mix you plan to hold during recovery. As of 2025, a broad equity index portfolio has delivered roughly 6–8% annualised nominal returns over multi-decade periods; a 60/40 balanced fund, around 5–6%; a high-yield savings account, 3–5%. These are long-run averages and should be treated as editable estimates — actual returns vary year to year and are not guaranteed. A conservative rate (4–5%) avoids underestimating recovery time.

The model assumes constant monthly contributions and a fixed return throughout the recovery period. It does not account for inflation (use a real rate = nominal rate minus ~2–3% if your target is in today's dollars), taxes on investment gains, or periods of zero earnings. The chart shows the month-by-month balance curve so you can see how compounding increasingly supplements contributions as the balance grows.