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ManagedFunds.nz

Tool

Monte Carlo projection

A single average-return line hides the thing that actually matters: returns vary year to year, and the order they arrive in changes where you land. This tool runs your investment 1,000 times with randomised returns and shows the full spread of outcomes — net of fees and PIE tax — plus how often it reaches your goal.

Inputs

Project the range of outcomes

Runs 1,000 simulated investment paths. Each month's return is drawn at random from a normal distribution around your expected return, so the result is a spread of possible balances — not a single line. Monthly compounding, annual fee deducted monthly, PIE tax applied annually at your PIR.

Volatility guide (long-run, illustrative): defensive/conservative ≈ 4–7%, balanced ≈ 8–11%, growth ≈ 12–16%, aggressive/single-sector ≈ 16%+. Match it to the FMA risk indicator (1–7) on the fund's page — higher risk indicator means wider swings.

Median outcome (P50)

$190,928

Half the simulations finished above this, half below — Year 20

Lower outcome (P10)

$130,252

1 in 10 paths finished below this — a poor-returns scenario

Upper outcome (P90)

$277,751

1 in 10 paths finished above this — a strong-returns scenario

Reached your goal

0%

0 of 1,000 paths reached $500,000

Range of outcomes by year

Spread from poor (P10) to strong (P90) returns

Each bar spans the 10th–90th percentile of simulated balances for that year; the darker notch marks the median (P50). The fan widens over time because uncertainty compounds.

Y1
$16,522
Y2
$23,112
Y3
$29,904
Y4
$37,335
Y5
$44,816
Y6
$52,548
Y7
$60,130
Y8
$68,083
Y9
$76,599
Y10
$85,285
Y11
$93,856
Y12
$103,613
Y13
$114,389
Y14
$124,423
Y15
$134,170
Y16
$144,698
Y17
$154,235
Y18
$165,687
Y19
$176,369
Y20
$190,928
P10–P90 range
Median (P50)

Caveats

  • This is a stochastic model, not a forecast. It shows a spread of hypothetical outcomes under your assumptions — it does not predict what your fund will actually do.
  • Returns are drawn from a normal distribution. Real markets have fat tails (crashes are more frequent and severe than a normal curve implies) and return-sequencing risk, so genuine worst cases can be worse than the P10 shown here.
  • Past performance is not a reliable indicator of future returns. Your expected-return and volatility inputs are assumptions, not promises.
  • PIE tax model is simplified — applied annually on positive net returns at your PIR. Real PIE tax accrues monthly with carry-forward of losses, so effective tax may be slightly lower in down years.
  • Fee assumed constant; some actively-managed funds also charge performance fees in strong-return years — check the PDS for the specific fund.
  • Results re-randomise on each input change, so the exact figures shift slightly run-to-run — that variability is the point of a Monte Carlo model.
  • This is general information only, not personalised financial advice. For advice see a licensed financial adviser.