With the volume of agency debt declining and foreign interest in mortgage-backed securities growing, Freddie Mac this week launched a new breed of mortgage security designed to tap into the emerging Asian demand for safe, dollar-denominated investments. Freddie’s $1.25 billion Class AE “Reference REMIC” R-001, which was priced this week at 75 basis points over the interpolated Treasury curve, is part of a larger offering that will include another $1 billion plus piece scheduled to…