The strong performance of jumbo mortgages originated in recent years is due to more than just focusing on borrowers with healthy credit scores, loan-to-value ratios and debt-to-income ratios, according to Moody’s Investors Service. The analysts said “soft” qualitative underwriting factors play a major role in jumbo performance. Qualitative factors considered by jumbo lenders include the absence of negative events in a borrower’s credit history, the number of unblemished lines of credit and ...