We assess the complicated reality of monetary policy transmission through mortgage markets by synthesizing the existing literature on the role of refinancing in policy implementation. After briefly reviewing mortgage market institutions in the U.S. and documenting refinance activity over time,...

In the U.S. mortgage market, private mortgage insurance (PMI) is mandated for high-leverage mortgages purchased by Fannie Mae and Freddie Mac to serve as a private market check on GSE risk-taking. However, we document that PMI firms dramatically expanded insurance on high-risk mortgages at the...