The number of periods and the rate must describe the same time interval.
Monthly and annual inputs
If each row represents a month, enter a monthly rate. If each row represents a year, enter an annual rate. The tool has no calendar or automatic rate conversion, so define your period before entering values.
Conversion example
A 12% effective annual growth assumption does not equal 1% compound monthly growth: 1.01^12 − 1 is about 12.68%. A monthly rate equivalent to 12% annually is (1.12^(1/12) − 1) × 100, about 0.9489%.
Document your assumptions
Include the period length and whether a rate is nominal or effective in your notes. The CSV period column contains counts, not dates. Rounding can cause a small difference between a converted-rate example and a full-precision calculation.
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