Why this matters
What this means.
The buffer changes the target portfolio without changing spending itself. It can show how extra caution changes the Financial Independence Year, but it does not remove uncertainty from the estimate.
Year impact
How this can move the year.
A larger buffer raises the target and can move the projected year later. A smaller buffer lowers the target and can move the projected year earlier.
How it is used
How the calculation uses it.
The calculation treats the buffer as a simple multiplier above the spending and withdrawal-rate target. Undefeated does not decide what buffer is right, and it does not model specific emergencies, insurance needs, tax shocks, cash reserves, or sequence-of-returns risk.
Estimate limits
What can make the estimate change.
The estimate may change if the uncertainty being represented is larger, smaller, or different from what a single multiplier can capture.