A junior risk analyst has been assigned by a risk manager to assess the prepayment risk for a portfolio of fixed-rate mortgages. As part of this assessment, the analyst needs to determine the conditional prepayment rate (CPR) for the portfolio, which begins with calculating the monthly prepayment for an individual mortgage. Consider a specific 30-year fixed-rate mortgage that originally amounted to USD 1,750,000, with monthly payments derived from an annual fixed interest rate of 8%. The borrower made a total monthly mortgage payment of USD 15,950.00, and the outstanding loan balance at the beginning of that month was USD 1,644,235.78. What is the precise calculation of the prepayment for that month?