https://www.efanniemae.com/sf/guides/ssg/annltrs/pdf/2010/sel1011.pdf
The GSE also outlined an expanded debt-to-income (DTI) ratio tolerance that the company says will lead to fewer loans having to be re-underwritten. Lenders will only be required to re-underwrite a loan after the initial underwriting decision has been made if the borrower discloses or the lender discovers changes that cause the DTI ratio to exceed 45 percent or to increase by 3 percentage points or more.