THE 1960s and 1970s were decades of enormous growth in the demand for single-family housing in the United States. The homeownership rate increased between 1960 and 1979 from 62 to 65 percent, and the quality of the average new home sold rose by over 25 percent. The increase in the homeownership rate is surprising because the numbers of young and single-person households, which historically have relatively low homeownership rates, grew much more rapidly than older, multiperson households, which have tended to have high homeownership rates. The increase in quality is surprising also because rising mortgage rates and relatively rapid increases in house prices doubled the real initial monthly mortgage payment on a house of constant quality. Thus it has been increasingly difficult for households to finance houses with constant quality, much less houses with higher quality.