660 yuan. According to the regulations of the People's Bank of China, the annual interest as of 2023 is 0.66%. Assume that the principal is P and the monthly interest rate is r. The formula of the monthly interest I is I equals P times r. According to the question conditions, P is equal to 100000 , the monthly interest rate is 6%6, which is 0.66%. It can be calculated by substituting it into the formula. Interest refers to the remuneration that money holders receive from borrowers for lending money or monetary capital, including interest on deposits, loans, and interest on various bonds.