Underwriting standards on jumbo mortgages tightened slightly in May compared with the previous month, according to the Mortgage Bankers Association. The results reversed six consecutive months of looser jumbo underwriting. Two-thirds of the 182 banks recently surveyed by the American Bankers Association said their originations in 2014 included non-qualified mortgages. Non-QMs accounted for 10 percent of the banks’ originations ... [Incluides three briefs]