Which of the following statements is NOT true about the Standard Default Assumption model of defaults. According to the SDA model of defaults, the mortgage default rate never goes to zero The graphical representation of the SDA model of default is the same shape as the graphical representation of the PSA model of prepayments The default rates predicted by the SDA default model do not depend on the maturity of the mortgage The SDA model of default predicts different default rates depending on time since origination of the mortgage According to the SDA model of defaults, a mortgage reaches the highest level of default rate in month 30 after origination