1, repayment method of equal principal and interest. Under this repayment method, the monthly repayment amount is fixed, including principal and interest. The calculation formula is: monthly payment = [loan principal× monthly interest rate× (1+monthly interest rate )× repayment months ]=[( 1+ monthly interest rate )× repayment months]; Monthly interest payable = loan principal × monthly interest rate ×[( 1+ monthly interest rate) repayment months -( 1+ monthly interest rate) (repayment month serial number-1)] ÷ [(1+monthly interest rate) repayment months -650. Monthly repayable principal = loan principal × monthly interest rate ×( 1+ monthly interest rate) ÷ (repayment month serial number-1)÷[( 1+ monthly interest rate) repayment months-1]; Total interest = repayment months × monthly repayment amount-loan principal.
2. Average capital repayment method. Under this repayment method, the monthly repayment principal is fixed, and the interest is calculated according to the remaining principal. The calculation formula is monthly payment = (loan principal ÷ repayment months)+(loan principal-accumulated repaid principal) × monthly interest rate; Monthly repayable principal = loan principal ÷ repayment months; Monthly interest payable = residual principal × monthly interest rate = (loan principal-accumulated principal repayment amount) × monthly interest rate; Total interest = repayment months × (total loan × monthly interest rate-monthly interest rate × (total loan ÷ repayment months) * (repayment months-1)÷2+ total loan ÷ repayment months).