Suppose the repayment is exactly one year (i.e. 12), that is, the one-time repayment is 654.38+10,000 yuan.

"average capital" model

Annual interest rate =5.73%, monthly interest rate = annual interest rate/12=0.4775%.

First, calculate the monthly repayment of principal.

Formula monthly repayment of principal = loan amount/total number of months?

Monthly repayment of principal = 500,000/240

Monthly repayment of principal = 2083.33 yuan.

Second, calculate the down payment.

Formula down payment = loan amount *[( 1/ total months)+monthly interest rate)]?

Down payment = 500,000 * [(1/240)+0.4775%)]

First repayment amount = 4470.83 yuan

Third, calculate the monthly decline.

Formula Monthly Decreasing Amount = Loan Amount/Total Months * Monthly Interest Rate

Monthly decline = 500,000 /240 * 0.4775%

Monthly decreasing amount =9.95 yuan

Fourth, calculate the total interest in the early and late stages.

Formula: total interest in the previous and later periods = monthly decreasing amount * (total months-paid months) * (total months-paid months-1)/2

The total interest in the earlier and later periods =9.95*228*227/2.

Total interest of the previous and later periods = 257,432.19 yuan.

5. Calculate the late down payment.

Formula 1 Remaining principal in later period = loan amount-(number of months paid back+1)* Monthly principal repayment-lump sum repayment amount.

The remaining principal in the later period = 500000-13 * 2083.33-100000.

The remaining principal in the later period = 372,965,438+06.67 yuan.

Formula 2 overdue monthly repayment of principal = overdue residual principal/(total months-paid months-1)

Monthly repayment of principal in later period = 372,965,438+06.67/227.

Repay the principal every month in the later period = 1, 642.80 yuan.

Formula 3 Interest on overdue down payment = overdue residual principal * monthly interest rate

Late interest and down payment = 372,965,438+06.67 * 0.4775%

Late interest and down payment = 1, 780.68 yuan.

Formula 4 overdue down payment = monthly overdue repayment principal+overdue down payment interest.

Late down payment = 1642.8+ 1780.68.

The first repayment amount in the later period = 3423.48 yuan.

Six, calculate the month-end decline.

Formula Decline of overdue months = overdue residual principal/(total months-paid months-1)* monthly interest rate.

Month-end monthly decline = 372,965,438+06.67/227 * 0.4775%

Month-end monthly decline =7.84 yuan

Seven, calculate the total interest in the later period.

Formula: total interest in later period = 1/2* remaining principal in later period * monthly interest rate * (total months-paid months)

Total interest in later period =1/2 * 372916.67 * 0.4775% * 228.

Total interest in later period = 202,997.19 yuan.

Eight, calculate the interest savings.

Interest expense saved = total interest in the original later period-total interest in the later period.

Savings interest expense = 257,432.6438+09-2097,338+09.

Interest expense saved = 54,435.00 yuan.

Results:

Assuming that the loan is paid off in 65,438+02 installments of 65,438+000,000.00 yuan at one time, the repayment amount in the next installment is 3,423.48 yuan, which will decrease by 7.84 yuan in the following months. This prepayment can save interest of 54,435.00 yuan.