Interest shortfalls on non-agency MBS have increased significantly in the past five months, according to research by Morningstar Credit Ratings. The servicing-related issue causes investors to absorb unpredictable losses and could result in downgrades of non-agency MBS. A sample of 2,858 non-agency MBS deals (21,727 tranches) examined by Morningstar in May and again in August showed a 38.0 percent increase in the number of deals with interest shortfalls. Some 18.6 percent of non-agency MBS deals examined by Morningstar for the August remittance period experienced a shortfall in at least one tranche. Shortfalls increased overall even though 21.8 percent of the shortfalls seen in March had...