Nominal interest refers to the amount of interest due at the end of a calculation period. Effective interest increases with the number of payments made. In other words, interest is often paid in instalments (for example, monthly or quarterly) before the end of the calculation period.
由于名义利率涉及的是在计算期限结束时到期的利率。而利率通常以月利率，季度利率等等计算且在计算期限结束之前分别到期。也就是说，利率通常是应该预支付的。这样实际利率便会随分期支付利率次数的增加而变化。