EAR = (1+ APR/Npery)^(npery)-1, or EAR = (1+APR/n)^n-1
APR = ((1+EAR)^(1/n)-1)*n
Effective Annual Interest Rate
The Effective Annual Interest Rate is a measure of interest that incorporates the compounding of interest and is frequently used to compare financial loans with different compounding terms.
where nominal_rate is the nominal interest rate (APR) and npery is the number of compounding periods per year.
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