Matching principal and interest method: loan principal: 200,000 yuan, assuming annual interest rate: 6.800%, loan life: 20 years; Monthly debt service: 65,438+0,526.68 yuan, total debt service: 366,403.2 yuan, * * interest payable: 65,438+0,664.03. 2 yuan. The interest paid in 1 month is:1133.33; The first 1 month principal repayment is: 393.35; Since then, the monthly interest repayment amount has decreased and the principal has increased. (without considering the adjustment of interest rate in the middle)