Probability of success (Monte Carlo)

The share of simulated paths in which your wealth never drops to 0 from the start of the full withdrawal phase (FIRE age) until the end age. 100% means: in none of 1,000 runs did the money run out early.

Fluctuations before your FIRE age (accumulation/Coast/Barista) deliberately do NOT count as "running out" – in those phases you are saving or earning extra income, and a temporary dip does not derail the plan. Only the load-bearing withdrawal phase is evaluated.