Answer: The annualized interest rate 1.99 is the annual interest rate 1.99 points, and the annual interest rate is 0.0 1.99 principal. The annual interest rate 1.99 points represents one yuan of principal, and the annual interest rate 1.99 points is 0.0 199 yuan, and the annualized interest rate = annual interest rate ÷ principal x 100%=0.0 199 yuan ÷/kloc. When the value of the principal is known, the corresponding annual interest can be calculated by substituting into the formula, and the annual interest =0.0 199.