Answer: A decrease in the average loan-to-value ratio of the mortgage pool

The correct answer is B. A decrease in the average loan-to-value ratio is likely to cause curtailments, which are partial prepayments, therefore increasing prepayments. This is because when the loan-to-value ratio decreases, borrowers have less outstanding debt relative to the value of their home, making it more likely that they will make additional payments towards their mortgage. This can be due to a variety of reasons, such as home price appreciation or additional payments made by the borrower. As a result, the overall prepayment rate on the mortgage-backed securities (MBS) portfolio increases. Option A is incorrect because a decrease in defaults usually leads to a decrease in prepayments. When fewer borrowers default on their loans, there is less incentive for others to prepay their mortgages, as they are not as likely to be facing financial hardship. Option C is incorrect because an increase in market interest rates typically leads to a decrease in prepayments. When interest rates rise, the cost of refinancing a mortgage becomes higher, making it less attractive for borrowers to prepay their existing mortgage. This is because they would need to secure a new loan at a higher interest rate, which could increase their monthly payments. Option D is incorrect because an increase in the supply of newly built housing can decrease the value of existing houses, which in turn slows down refinancing activity for drawing on home equity. When the housing market becomes saturated with new homes, the demand for existing homes may decrease, leading to a potential drop in home prices. This makes it less advantageous for homeowners to refinance their mortgages, as they may not be able to access as much home equity as they could if house prices were higher. Consequently, this can lead to a decrease in prepayments on the MBS portfolio.

Author: LeetQuiz Editorial Team