Upfront Tax: A % of principal paid before any growth. Remaining = starting balance.
Annual Compounding: Interest = Balance × Rate each year.
First-Year Interest (Tab 2): your natural Year-1 income if principal is untouched.
4% Fixed Withdrawal (Tab 2): withdraw 4% of your post-tax starting balance as a fixed dollar amount each year. Note: this is more conservative than the Bengen 4% rule, which inflates the withdrawal annually — not modeled here.
Inflation Adj. (Tab 2): nominal ÷ (1 + inflation_rate)^years. Discounts the Year-1 nominal withdrawal back by N years of inflation to show its purchasing power in Year-N dollars (uses the inflation rate you enter, NOT the investment rate).
Reinvestment (Tab 3): fixed annual addition on top of compounding — added at end of year (annuity-immediate), so Year-1 contribution earns interest starting Year 2.
Comparison (Tab 4): side-by-side view of Base / Spending / Reinvestment scenarios over time.
Post-Tax Start
—
Final Balance
—
Total Interest
—
Growth Multiple
—
| Year | Beginning | Interest | Ending |
|---|
First-Year Interest
—
Post-tax principal × annual rate
Use 4% Fixed Withdrawal
Withdraw 4% of post-tax starting balance each year (fixed nominal dollar amount, not inflation-adjusted)
4% Fixed Withdrawal on Starting Balance
—
Annual spend = 4% × post-tax start (—)
vs. First-year interest spending: —
Percent of first-year interest to spend
Adjust for Inflation
Show amounts in today's purchasing power
Nominal ÷ (1 + inflation rate)^years = Year-N purchasing power
Annual Spend
—
Monthly
—
Weekly
—
Daily
—
Reinvested: — per year compounds further.
Spend
—
Reinvest / Remaining
—
—
Unspent First-Year Interest
—
= First-Year Interest × (100% − Spending %)
To reinvest more, reduce your Spending % on the Spending Planner tab.
4% Rule active: Reinvestment is not defined when using the 4% Safe Withdrawal Rule, because that method draws from starting principal rather than from first-year interest. Switch back to Spending % on the Spending Planner tab to enable reinvestment growth calculations.
Final Balance
—
vs. Base Growth
—
Total Reinvested
—
Total Interest
—
| Year | Beginning | Reinvested | Interest | Ending |
|---|
Base Growth
—
Pure compounding, no additions
Spending Scenario
—
After annual withdrawals
Reinvestment
—
With annual additions
| Scenario | Final Balance | vs. Base |
|---|