Fannie Mae and Freddie Mac issued $44.8 billion in single-family mortgage-backed securities during the month of May, a slight 1.3 percent dip from April, but it reversed the brief rebound following a year-long streak of declines, according to an Inside The GSEs analysis. However, May’s MBS issuance was down a much steeper 62.4 percent from the same period a year ago. Top-ranked Wells Fargo’s Fannie and Freddie securitization, at $5.97 billion, dropped by 4.9 percent on a monthly basis and by 73.6 percent year-to-date.