Savings target projection
Compare a future savings target with your starting money and monthly contributions. See both nominal money and purchasing power under your assumptions.
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Retirement withdrawals and asset duration
Estimate how long assets can cover spending after a fixed income. Compare beginning-of-month and end-of-month withdrawal timing.
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Full years of expenses covered
23years
Under these assumptions, funds cover about 23 full years; the next month has a shortfall. Future returns are not guaranteed.
Full months of expenses covered276 months
Balance at the end or before the first shortfall21,209.67 TWD
Shortfall in the first insufficient month16,097.31 TWD
Total paid7,624,186.76 TWD
Calculation details (23 rows)
| Full year | Cumulative net withdrawals (TWD) | Year-end balance (TWD) |
|---|---|---|
| 1 | 240,000 | 5,877,407.87 |
| 2 | 487,200 | 5,745,086.13 |
| 3 | 741,744 | 5,602,694.63 |
| 4 | 1,003,778.88 | 5,449,883.52 |
| 5 | 1,273,454.46 | 5,286,292.97 |
| 6 | 1,550,923.55 | 5,111,552.92 |
| 7 | 1,836,342.02 | 4,925,282.82 |
| 8 | 2,129,868.86 | 4,727,091.39 |
| 9 | 2,431,666.24 | 4,516,576.26 |
| 10 | 2,741,899.56 | 4,293,323.76 |
| 11 | 3,060,737.55 | 4,056,908.62 |
| 12 | 3,388,352.3 | 3,806,893.62 |
| 13 | 3,724,919.35 | 3,542,829.33 |
| 14 | 4,070,617.74 | 3,264,253.8 |
| 15 | 4,425,630.09 | 2,970,692.19 |
| 16 | 4,790,142.69 | 2,661,656.49 |
| 17 | 5,164,345.55 | 2,336,645.16 |
| 18 | 5,548,432.46 | 1,995,142.8 |
| 19 | 5,942,601.11 | 1,636,619.77 |
| 20 | 6,347,053.13 | 1,260,531.84 |
| 21 | 6,761,994.19 | 866,319.81 |
| 22 | 7,187,634.07 | 453,409.18 |
| 23 | 7,624,186.76 | 21,209.67 |
Net withdrawal = max(expenses − fixed income, 0). Interest uses (1 + annual return)^(1/12). Choose withdrawal at the start of the month or interest first at month-end. Expenses adjust after each full 12 months. Income above expenses is not reinvested. Results count full months affordable; the first unaffordable month has its shortfall listed separately. Not running out only means funds last within the observation period, not forever or with guaranteed investment returns.
Method and scope
Net withdrawal is the larger of expenses minus income and zero. Monthly interest uses (1 plus effective annual return) to the power 1/12; expenses increase after every 12 months, while income stays fixed.
The result counts fully payable months and separately shows any shortfall in the first unaffordable month. Money remaining at the observation limit only means the selected period was covered.
Income exceeding expenses is not added back to assets. Constant returns and expense growth are assumptions, not investment forecasts; reaching the time limit does not prove that withdrawals are sustainable forever.
What this helps you do
Estimate how long assets can cover spending after a fixed income. Compare beginning-of-month and end-of-month withdrawal timing.
What to enter
Start with available assets (twd), then fill the other relevant fields in the units shown. The field hints explain the required format and examples.
How the calculation works
Net withdrawal is the larger of expenses minus income and zero. Monthly interest uses (1 plus effective annual return) to the power 1/12; expenses increase after every 12 months, while income stays fixed.
Worked example
With TWD 120,000 assets, TWD 15,000 monthly spending, TWD 5,000 income and 0% return and inflation, assets cover 12 complete months. The next month needs TWD 10,000 more.
Understanding the answer
The result counts fully payable months and separately shows any shortfall in the first unaffordable month. Money remaining at the observation limit only means the selected period was covered.
Scope and limitations
Income exceeding expenses is not added back to assets. Constant returns and expense growth are assumptions, not investment forecasts; reaching the time limit does not prove that withdrawals are sustainable forever.