We conduct an empirical analysis of the Federal Reserve's large-scale asset purchases (LSAPs) on MBS yields and mortgage rates. The Federal Reserve's accumulation of MBS and Treasury securities lowered MBS yields and mortgage rates by more than what would have been suggested by changes in market...

Measured as yield spreads against AAA corporate bonds, the convenience premium of agency MBS averages 47 basis points over 1995 - 2021, about half of the long-term-Treasury convenience premium. Both MBS convenience premium and issuance amount depend on mortgage rate negatively, consistent with a...