Mortgage choice and the pricing of fixed-rate and adjustable-rate mortgages

In the United States throughout 2009, the share of adjustable-rate mortgages among total mortgage originations was very low, apparently reflecting the attractive pricing of fixed-rate mortgages relative to ARMs. Government policy could have changed the relative attractiveness of the fixed-rate mortgages and ARMs, thereby shifting the market share of these two housing finance instruments. ; This Economic Letter reviews some of the factors determining consumer mortgage choices. It shows that ARM share has declined in ways that parallel the behavior of several key mortgage market interest rates. These developments have coincided with, among other things, Fed intervention in the market through large-scale MBS purchases. Thus, the Fed program, while supporting the functioning of the residential mortgage market overall, could have affected the composition of the mortgage market. To help understand this dynamic, this Letter estimates what the ARM share might have been under alternative scenarios in which fixed mortgage rates were higher, which would likely have been the case if the Fed had not been intervening in the market to the extent that it did.