Our mortgage insurance incurred losses are driven primarily by new mortgage insurance defaults and adverse development in the assumptions used to determine our loss reserves. Establishing loss reserves in our businesses requires significant judgment by management with respect to the likelihood, magnitude and timing of anticipated losses. This judgment has been made more difficult in the current period of prolonged economic uncertainty. Our estimate of the percentage of defaults that ultimately will result in a paid claim (the “default to claim rate”) is a significant assumption in our reserving methodology. Our assumed aggregate weighted average default to claim rate (which incorporates the expected impact of rescissions and denials) was approximately 43% for 2011 and 46% as of September 30, 2012. Assuming all other factors remain constant, for each 1% increase in our aggregate weighted average default to claim rate as of September 30, 2012, incurred losses would increase by approximately $56 million. Radian Guaranty’s statutory capital would be reduced by the after-tax impact of these incurred losses. Our level of incurred losses is also dependent on our estimate of anticipated rescissions and denials, including our estimate of the likely number of successful challenges to previously rescinded policies or claim denials, among other assumptions. If the actual losses we ultimately realize are in excess of the loss estimates we use in establishing loss reserves, we may be required to take unexpected charges to income, which could adversely affect our statutory capital position and increase Radian Guaranty’s risk-to-capital ratio.
If Radian Guaranty is not in compliance with a state’s applicable Statutory RBC Requirement, it may be prohibited from writing new business in that state until it is back in compliance or it receives a waiver of or similar relief from the requirement from the applicable state insurance regulator, as discussed in more detail below. In those states that do not have a Statutory RBC Requirement, it is not clear what actions the applicable state regulators would take if a mortgage insurer fails to meet the Statutory RBC Requirement established by another state. Accordingly, if Radian Guaranty fails to meet the Statutory RBC Requirement in one or more states, it could be required to suspend writing business in some or all of the states in which it does business. In addition, the GSEs and our mortgage lending customers may decide not to conduct new business with Radian Guaranty (or may reduce current business levels) or impose restrictions on Radian Guaranty while its risk-to-capital ratio remained at elevated levels. The franchise value of our mortgage insurance business would likely be significantly diminished if we were prohibited from writing new business or restricted in the amount of new business we could write in one or more states.