$20,000 for 40 years at returns from 4% to 10%
| Return | Balance | Multiple | In today’s dollars |
|---|---|---|---|
| 4% | $96,020 | 4.8× | $29,436 |
| 5% | $140,800 | 7.0× | $43,163 |
| 6% | $205,714 | 10.3× | $63,063 |
| 7% | $299,489 | 15.0× | $91,810 |
| 8% | $434,490 | 21.7× | $133,196 |
| 10% | $905,185 | 45.3× | $277,491 |
Year by year at 7%
| Year | Put in so far | Balance | In today’s dollars |
|---|---|---|---|
| 1 | $20,000 | $21,400 | $20,777 |
| 2 | $20,000 | $22,898 | $21,584 |
| 3 | $20,000 | $24,501 | $22,422 |
| 5 | $20,000 | $28,051 | $24,197 |
| 10 | $20,000 | $39,343 | $29,275 |
| 15 | $20,000 | $55,181 | $35,418 |
| 20 | $20,000 | $77,394 | $42,851 |
| 25 | $20,000 | $108,549 | $51,843 |
| 30 | $20,000 | $152,245 | $62,723 |
| 35 | $20,000 | $213,532 | $75,886 |
| 40 | $20,000 | $299,489 | $91,810 |
The range in 1,000 simulated markets
A 7% average does not arrive as 7% every year. In 1,000 simulated sequences of returns averaging 7% with 12% volatility, this is where $20,000 ended up: 1 in 10 markets finished below the first figure, half below the middle one, and 1 in 10 above the last.
| After | Weak (1 in 10 lower) | Middle | Strong (1 in 10 higher) |
|---|---|---|---|
| 20 years | $34,793 | $66,748 | $128,357 |
| 40 years | $91,096 | $233,849 | $590,679 |
The middle of the simulation sits below the steady 7% figure of $299,489 because ups and downs cost compounding: a 20% loss needs a 25% gain to get back.
What $299,489 would pay in retirement
At a 4% first-year withdrawal, $299,489 pays about $11,980 a year, $998 a month, before tax; in today’s dollars that is about $3,672 a year. How long a balance near it lasts at each withdrawal: how long $300,000 lasts. To stop saving early and let growth do the rest, see Coast FIRE numbers by age.
$20,000 for other terms
| Years | Balance | In today’s dollars |
|---|---|---|
| $20,000 for 5 years | $28,051 | $24,197 |
| $20,000 for 10 years | $39,343 | $29,275 |
| $20,000 for 15 years | $55,181 | $35,418 |
| $20,000 for 20 years | $77,394 | $42,851 |
| $20,000 for 25 years | $108,549 | $51,843 |
| $20,000 for 30 years | $152,245 | $62,723 |
| 40 years | $299,489 | $91,810 |
| $20,000 for 50 years | $589,141 | $134,387 |
Other amounts for 40 years
$1,000: $14,974, $5,000: $74,872, $10,000: $149,745, $25,000: $374,361, $50,000: $748,723, $100,000: $1,497,446, $200,000: $2,994,892, $250,000: $3,743,614, $500,000: $7,487,229, $1,000,000: $14,974,458, $2,000,000: $29,948,916.
How it is worked out
Monthly amounts are deposited at the end of each month and compounded monthly at the rate that equals the annual return; lump sums compound once a year. The headline return is 7% a year, the Trinity-style average the site’s retirement pages use; stock-heavy portfolios have averaged more over long periods and bond-heavy ones less, which is why every page shows 4% to 10%. Today’s dollars divide by 3% inflation a year. The range comes from 1,000 simulated sequences of yearly returns averaging 7% with 12% volatility, with each year’s deposits added through the year. Fees and taxes are not taken out. More on the methodology page.