你可以参考看看网上关于Reducing Balance Method的算法,也许可以帮到你。
Reducing Balance Method
This method is mainly used to calculate the interest payable for housing / mortgage / property loans which you can find at our home loan comparison tool and other interest payable such as overdraft (OD) facilities, and credit cards. You only pay interest on the remaining loan balance. A reducing balance interest calculation formula can be represented like this:
Interest Payable per Installment = Interest Rate per Installment * Remaining Loan Amount
参考:
https://loanstreet.com.my/learning-centre/interest-calculation-reducing-balance-flat-interest
http://www.calculatoredge.com/finance/dreducing.htm
http://www.double-entry-bookkeeping.com/depreciation/reducing-balance-depreciation-calculator/



