How likely your money is to last

What the number means

Each run is your whole plan, year by year, with each year's markets taken from a random year of US history between 1928 and 2025: stocks, bonds, cash and gold as they moved that year, and inflation. They're applied as ups and downs around your plan's own returns (stocks 7% a year unless you set yours), so a typical run looks like your plan. You stop working when your plan says, whatever markets do. The percentage is the share of runs where the money lasts to 95.

A bad run

The worst 1 run in 10: the age the money runs out then, or that it lasts even then.

Replayed through history

Your retirement run through every stretch of real history since 1928 as long as it is, years in order: how many it survives, and which starting years it doesn't (often 1929, 1937 and the late 1960s, when high inflation followed).

Range of outcomes

On the chart, the shaded fan around your line: the middle half of runs (darker) and 1 in 10 to 9 in 10 (lighter), in the chart's dollars. The best runs can go off the top. Turn it off under Chart display > Range of outcomes.

When markets fall

Under the odds, pick how your spending in retirement follows markets:

Keep spending

What you planned, rising with inflation, whatever markets do. The plan everywhere else on the page.

Guardrails

Spend 10% less when your withdrawals climb 20% above where they started (as a share of the portfolio), and 10% more when they fall 20% below.

% of portfolio

Spend your withdrawal rate (4% at 25x) of the portfolio each year, after tax. It never runs out, but your spending moves with markets.

Floor & ceiling

The same share of the portfolio, but never below 80% or above 125% of what you planned.

Healthcare, loans, kids and life events are always paid in full: the rules only move your lifestyle spending. Compare all four runs each rule on the same markets and shows its chance, and the spending a year in a typical run and in a bad one, in today's dollars. The rule you pick also shapes the plan itself: the table shows each year's spending under it.

Reading it

• For a long early retirement, 85% or more is strong. Under 70%, try spending a little less, working a little longer, or a flexible rule, and watch the number move.
• The odds use your plan's returns, below history's average (stocks 7% a year before inflation, about 4% after, against about 6.8% since 1928), so they're more cautious than studies that replay history as it happened. Set your own return per account under Portfolio Assets.
• Crypto swings 2.5 times as hard as stocks; bonds follow 10-year Treasuries, cash follows Treasury bills, metals follow gold. Homes and other things you own don't swing.
• Scenarios you compare get their own Chance it lasts, from 200 runs each.