A straight-line projection hides bad years. This runs 2,000 simulated markets with random yearly returns, and counts how many times your money lasts. Your withdrawal rises with inflation each year.
Chance your money lasts: 70.3 %
Your answer
Chance your money lasts70.3 %
Median ending balance (today's money)
$357,559.22
Poor market (10th percentile)
$0.00
Strong market (90th percentile)
$1,909,550.07
First-year withdrawal rate
4 %
Portfolio in today's money
Strong market
Median
Poor market
Show the numbers
Portfolio in today's money
Year
Strong market
Median
Poor market
0
$1,000,000.00
$1,000,000.00
$1,000,000.00
1
$1,131,597.21
$992,931.36
$851,061.67
2
$1,181,733.88
$973,832.35
$786,771.49
3
$1,220,580.00
$965,286.73
$734,638.25
4
$1,275,400.68
$944,227.94
$683,458.19
5
$1,302,685.41
$930,502.21
$648,683.95
6
$1,338,834.34
$910,967.93
$605,232.01
7
$1,401,405.44
$900,327.51
$565,486.04
8
$1,417,927.36
$891,696.02
$528,927.19
9
$1,449,518.34
$868,085.83
$496,042.93
10
$1,467,078.28
$846,022.96
$459,597.06
11
$1,497,551.76
$829,409.51
$423,099.85
12
$1,490,083.02
$804,278.51
$377,107.34
13
$1,517,858.45
$787,105.60
$341,771.43
14
$1,529,586.38
$777,268.35
$310,020.18
15
$1,551,580.04
$760,944.43
$271,695.96
16
$1,580,740.75
$732,012.19
$238,482.28
17
$1,609,675.72
$706,838.04
$201,263.61
18
$1,639,139.38
$687,870.77
$166,510.60
19
$1,697,683.35
$659,971.69
$125,127.97
20
$1,709,370.40
$638,018.25
$87,705.73
21
$1,737,553.03
$608,891.03
$50,393.68
22
$1,746,049.89
$580,719.20
$11,097.07
23
$1,793,819.02
$556,338.27
$0.00
24
$1,785,708.04
$540,973.17
$0.00
25
$1,790,912.98
$510,240.90
$0.00
26
$1,834,870.60
$484,341.18
$0.00
27
$1,848,264.34
$449,361.20
$0.00
28
$1,849,205.18
$416,590.94
$0.00
29
$1,916,960.21
$382,316.83
$0.00
30
$1,909,550.07
$357,559.22
$0.00
A model, not a forecast. Returns here are independent from year to year and follow a bell curve, while real markets can have longer slumps and sharper falls. Taxes and fees are not included. The same inputs always give the same result.
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How we worked it out
Updated as you change the numbers.
Each simulated year: take the withdrawal, raised for inflation, then apply a random return.
A run succeeds if money remains at the end. The answer is the share of 2,000 runs that succeed.
Method and assumptions
Returns are drawn from a normal distribution with your average and standard deviation. Withdrawals happen at the start of each year. Balances are shown in today's money by removing inflation. A fixed random seed keeps results repeatable.
Questions
What is a good Monte Carlo success rate?
There is no official target. A higher rate means fewer simulated markets ran out of money, but it can also mean spending less than you could. Treat it as a guide and review your plan each year.
Method and figures checked on October 31, 2026. Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.
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