How much principal before the yield covers your life? Compute your number, your coverage today, and — at your current pace — your years to go.
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monthly expenses × 12 ÷ net annual yield — a perpetuity: principal whose yield equals your burncurrently invested ÷ FIRE numbersolved numerically — smallest n where compounding of current capital plus monthly investments reaches the numberOne assumption carries everything: the net yield. It must already be net of tax and fees, and it should be a yield you can defend for decades — not last year's best trade. Inflation is not modeled separately; fold it into a conservative yield.