The annual interest in this case is 38,400 yuan.
A loan of 400,000 yuan with an interest rate of 8% means a monthly interest rate of 0.8. The monthly interest is 3,200 yuan, which is 38,400 yuan a year. The specific calculation formula is: interest = principal × interest rate × deposit term.
Different banks have different loan types, and loan interest rates will also vary. Loan interest needs to be calculated based on the loan amount, term, interest rate, and repayment method.