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What does money sent home do to the plan?

Support share is money sent home over a year, divided by income. Savings rate is annual savings divided by income. A second FIRE timeline asks what changes if that support is saved instead and removed from spending. The 4% withdrawal rate is an estimate, not advice.

Sent home5.0%

Share of income sent home

5.0%

$3,000 a year.

Savings rate

15.0%

If that support were saved instead, the savings rate would be 20.0%.

Years to a 4% FIRE number

24 years

FIRE number $900,000 at your current spending and savings.

If the support were saved instead

21 years

Spending falls to $33,000 and savings rise to $12,000. FIRE number $825,000. Most of any speedup is the smaller target.

Track on iOSTrack on AndroidSee Pro forecasts

How this is calculated

Assumptions

  • Annual support = monthly amount x 12. Share of income = annual support / annual income.
  • Savings rate = annual savings / annual income. This assumes the support is not already inside the savings figure.
  • FIRE number = annual spending / 0.04. Each year the balance grows by the return you enter, then savings are added, for up to 60 years.
  • The second timeline removes the annual support from spending and adds it to savings. It is a what-if, not a suggestion to stop supporting family.
  • The 4% rate is a historical US planning figure. It is not a promise, and it ignores tax, fees, and a different market.

Worked example

Income 6,000,000 NGN. Support 150,000 NGN a month, which is 1,800,000 NGN a year, or 30% of income. Savings 900,000 NGN, a 15% savings rate. Spending 3,600,000 NGN includes the support, so the 4% FIRE number is 90,000,000 NGN. From 8,000,000 NGN, saving 900,000 NGN a year at 7% takes about 24 years. If the support were saved instead, spending is 1,800,000 NGN (FIRE number 45,000,000 NGN) and savings are 2,700,000 NGN, about 9 years.

Sources

  • William P. Bengen, “Determining Withdrawal Rates Using Historical Data,” Journal of Financial Planning, October 1994. The 4% figure is a research result about US portfolios, used here only as the withdrawal rate in the timeline.

Educational software only. This is not financial, tax, or investment advice. Markets, inflation, fees, and your spending can all miss the model.

Last reviewed October 20, 2026 by Francis Eshun, Founder of Iron Wealth. He built the on-device tracker these pages describe. Iron Labs.

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