应计因子
应计因子由两个部分构成。第一个部分运用计日惯例来决定升值阶段的天数，也将用作计算升值原因时的分子，第二个部分是运用计日惯例来决定一个完整期限中需要多少天，也将用作计算升值原因时的分母。
Accrual Factor
Repsents the fraction of a year in a given period. There are two components that make up an accrual factor. The first component uses a day count convention to determine how many days fall in the accrual period, which will be the numerator in the calculation of the accrual factor. The second component is a day count convention to determine the number of days that make up a full period, which will be the denominator in the calculation of the accrual factor.