Morningstar Credit Ratings changed the way it rates residential MBS to allow credit for mortgage insurance. After getting a number of inquiries about the use of mortgage insurance in new MBS, the firm said it decided to enhance its methodology to provide a clearer framework for how the ratings agency approaches mortgage insurance. While mortgage insurance does not necessarily affect a borrower’s probability of default, it may decrease loss severities, according to Morningstar. “Our methodology now gives credit to mortgage insurance in some cases up to the AAA ratings level,” said Brian Grow, managing director of RMBS for Morningstar. “MI’s potential impact on default is...