Participants in the non-agency mortgage-backed security market are concerned about the strength of the sector as interest rates and other pricing metrics have increased significantly in recent weeks. When the 10-year Treasury rate started to rise recently and the mortgage interest rate spread out by 20 basis points, the non-agency MBS market spread out by 50 basis points, said Lewis Ranieri, chairman of Ranieri Partners, at a forum hosted by the Bipartisan Policy Center last week. And given theres ...