After decades of relative stability, the rate of U.S. homeownership began to surge in the mid-1990s, rising from 64% in 1994 to a peak of 69% in 2004, near which it has hovered ever since . . . [S]ome of the explanation likely stems from innovations in the mortgage market that resulted in greater access to credit, lower down payment requirements, and easy and low-cost access to the equity in a house, which makes homeownership more attractive.
Doms, Mark and Meryl Motika. 2006. "The Rise of Homeownership." Federal Reserve Bank of San Francisco Economic Letter (3 November).
Thanks to an old Timothy Taylor column in the Journal of Economic Perspectives