How Resilient are Mortgage Backed Securities to Collateralized Debt Obligation Market Disruptions?

The mortgage-backed securities (MBS) market has experienced significant changes over the past couple of years. Non-agency ("private label") securities, which are not guaranteed by the government or the government sponsored enterprises, now account for the majority of MBS issued. In this report, we review the rise of collateralized debt obligations (CDOs), the relaxation of lending standards, and the implementation of loan mitigation practices. We analyze whether these structural changes have created an environment of understated risk to investors of MBS. We also measure the efficacy of ratings agencies when it comes to assessing market risk rather than credit risk. Our findings imply that even investment grade rated CDOs will experience significant losses if home prices depreciate. We conclude by providing several policy implications of our findings.