Servicer-advance rates on vintage non-agency MBS have been up and down in recent quarters, showing further variances based on the servicer and issuer. The fluctuations have made it difficult to project valuations for certain securities, but industry analysts suggest that as mortgage performance continues to improve, servicer-advance rates will stabilize. The rate at which servicers advanced missed borrower payments on mortgages in non-agency MBS decreased slightly on a quarterly basis in the first quarter of 2014 after a gain the previous quarter, according to Fitch Ratings. Pooling and servicing agreements for non-agency MBS require servicers to continue making advance payments until the payments are deemed non-recoverable. Non-agency MBS values are...