TY - JOUR AU - Mian,Atif AU - Sufi,Amir TI - The Consequences of Mortgage Credit Expansion: Evidence from the 2007 Mortgage Default Crisis JF - National Bureau of Economic Research Working Paper Series VL - No. 13936 PY - 2008 Y2 - April 2008 UR - http://www.nber.org/papers/w13936 L1 - http://www.nber.org/papers/w13936.pdf N1 - Author contact info: Atif R. Mian University of California, Berkeley Haas School of Business 545 Student Services Berkeley, CA 94720 Tel: 510/643-1425 Fax: 510/643-1425 E-Mail: atif@haas.berkeley.edu Amir Sufi University of Chicago Booth School of Business 5807 South Woodlawn Avenue Chicago, IL 60637 Tel: 773/702-6148 Fax: 773/702-0458 E-Mail: amir.sufi@chicagobooth.edu AB - We demonstrate that a rapid expansion in the supply of mortgages driven by disintermediation explains a large fraction of recent U.S. house price appreciation and subsequent mortgage defaults. We identify the effect of shifts in the supply of mortgage credit by exploiting within-county variation across zip codes that differed in latent demand for mortgages in the mid 1990s. From 2001 to 2005, high latent demand zip codes experienced large relative decreases in denial rates, increases in mortgages originated, and increases in house price appreciation, despite the fact that these zip codes experienced significantly negative relative income and employment growth over this time period. These patterns for high latent demand zip codes were driven by a sharp relative increase in the fraction of loans sold by originators shortly after origination, a process which we refer to as "disintermediation." The increase in disintermediation-driven mortgage supply to high latent demand zip codes from 2001 to 2005 led to subsequent large increases in mortgage defaults from 2005 to 2007. Our results suggest that moral hazard on behalf of originators selling mortgages is a main culprit for the U.S. mortgage default crisis. ER -