Equal principal and interest repayment method: repay the loan principal and interest in equal amount every month, in which the interest decreases month by month and the principal increases month by month.

Average principal repayment method: equal repayment of principal every month. When the principal is reduced, the monthly interest is also reduced, and the monthly repayment amount is also reduced accordingly.

Calculation formula of equal principal and interest: [loan principal × monthly interest rate ×( 1 monthly interest rate) repayment months ]≤[( 1 monthly interest rate) repayment months-1] average fund calculation formula: monthly repayment amount = (loan principal/repayment months) (principal-accumulated amount of repaid principal).

For example, suppose you buy a house for the first time with a loan of 200,000 yuan for 20 years. Compare the differences between the two loan methods: the matching principal and interest repayment method is 200,000 yuan, the interest rate is 15%, the monthly repayment is 1325.33, the total repayment is 3 1.8 1.00000 yuan, and the interest is1.8. The average repayment method is 35 1 per month in August, 2000. The total repayment amount is 3010.4 million yuan, and the interest is1.10.4 million yuan.

Second, the calculation method of the repayment amount of commercial mortgage loans

1. There are two repayment methods: equal principal and interest repayment method and average capital repayment method.

2. Formula of debt service method: monthly repayment amount = loan principal × monthly interest rate ×( 1 interest rate )× repayment months /[( 1 interest rate )× repayment months]

3. Formula of principal repayment method: monthly repayment amount = (loan principal ÷ repayment months) (principal-accumulated amount of repaid principal) × monthly interest rate.

4. Monthly repayment amount = loan principal × monthly interest rate ×( 1 interest rate )× repayment months /[( 1 interest rate )× repayment months-1]. This is the repayment method of equal principal and interest, so you have to pay 1526 yuan every month, calculated according to the latest bank benchmark interest rate. 1520240 months =364800. This is interest with interest. Use 364800-200000= 164800. This is the interest you pay back to the bank after 20 years of loan.