The 4% Rule and the Rule of 72: Origins, Examples and Limits
Two rules of thumb every retirement planner uses, where they came from, and what to keep in mind.
Financial Articles
Guides and formula histories for our financial calculators.
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Kelly Criterion: History, Formula and Fractional Kelly
The bet-sizing formula from a 1956 Bell Labs paper: how it works, why it is aggressive and how to tame it.
RMD Rules Explained: Age 73, Age 75 and What Changed
RMD age is now 73 and rising to 75. Here is how the rules changed and how the calculation works.