Fannie Mae and Freddie Mac purchased $127.7 billion of single-family loans last year that failed to meet the baseline qualified-mortgage standard set by the Consumer Financial Protection Bureau, according to a new analysis by Inside The GSEs. Under the agency’s ability to repay rule, the GSEs can ignore the restriction that qualified mortgages must have a debt-to-income ratio of 43 percent or less. This so-called agency “patch” was set up to last for seven years, or until 2021, as long as Fannie and Freddie remain in conservatorship or receivership. In other regards, such as the 30-year limit on maximum loan term and the prohibition on interest-only payments, the GSEs...