|FEDERAL NATIONAL MORTGAGE ASSOCIATION FANNIE MAE filed this Form 10-Q on 08/03/2017|
servicers may have a greater reliance on third-party sources of liquidity and may, in the event of significant increases in delinquent loan volumes, have less financial capacity to advance funds on our behalf or satisfy repurchase requests or compensatory fee obligations. In addition, regulatory bodies have been reviewing the activities of some of our largest non-depository servicers. See “Risk Factors” in our 2016 Form 10-K for a discussion of the risks of our reliance on servicers.
Our five largest single-family mortgage sellers, including their affiliates, accounted for approximately 34% of our single-family business acquisition volume in the first half of 2017, compared with approximately 28% in the first half of 2016. Our largest mortgage seller is Wells Fargo Bank, N.A., which, together with its affiliates, accounted for approximately 16% of our single-family business acquisition volume in the first half of 2017, compared with approximately 13% in the first half of 2016.
We acquire a portion of our business volume directly from non-depository and smaller depository financial institutions that may not have the same financial strength or operational capacity as our largest mortgage seller counterparties. We could be required to absorb losses on defaulted loans that a failed mortgage seller is obligated to repurchase from us if we determine there was an underwriting eligibility breach.
We use various types of credit guarantors to manage our mortgage credit risk, including mortgage insurers, credit insurance risk transfer counterparties, financial guarantors, and multifamily lenders with risk sharing.
We are generally required, pursuant to our charter, to obtain credit enhancements on single-family conventional mortgage loans that we purchase or securitize with LTV ratios over 80% at the time of purchase. We use several types of credit enhancements to manage our single-family mortgage credit risk, including primary and pool mortgage insurance coverage. Table 30 displays our risk in force for mortgage insurance coverage on single-family loans in our guaranty book of business and our insurance in force for our mortgage insurer counterparties, excluding insurance coverage provided by federal government entities and credit insurance obtained through CIRT deals. The table includes our top nine mortgage insurer counterparties, which provided over 99% of our total mortgage insurance coverage on single-family loans in our guaranty book of business as of June 30, 2017 and December 31, 2016. In addition, for our mortgage insurer counterparties not approved to write new business, we have provided the percentage of their claims payments the counterparties are currently deferring based on the direction of their state regulators, referred to as their deferred payment obligation. As of June 30, 2017 and December 31, 2016, less than 1% of our total risk in force mortgage insurance coverage was pool insurance. In addition, approximately 1% of our total insurance in force mortgage insurance coverage was pool insurance as of June 30, 2017 and December 31, 2016.
When we estimate the credit losses that are inherent in our mortgage loans and under the terms of our guaranty obligations we also consider the recoveries that we expect to receive on primary mortgage insurance, as mortgage insurance recoveries would reduce the severity of the loss associated with defaulted loans. The amount by which our estimated benefit from mortgage insurance reduced our total combined loss reserves was $1.1 billion as of June 30, 2017 and $1.4 billion as of December 31, 2016.