Introduction
The US subprime mortgage crisis was one of the first indicators of the late-2000s financial crisis, characterized by a rise in subprime mortgage holes and foreclosures, and the resulting decline of securities backing mortgages. Approximately 80% of U.S. mortgages issued to subprime borrowers were adjustable-rate mortgages. After U.S. house sales prices peaked in mid-2006 and began their steep decline forthwith, refinancing became more difficult. As adjustable-rate mortgages began to reset at higher interest rates, mortgage crisis soared. Securities backed with mortgages, including subprime mortgages, widely held by financial firms, lost most of their value. Global investors also drastically reduced purchases of mortgage-backed debt and other securities as part of a decline in the capacity and willingness of the private financial system to support lending. Concerns about the safety of U.S. credit and financial markets led to tightening credit around the world and slowing economic growth in the U.S. and Europe.
1. Background—mortgage market The immediate reason or trigger of the crisis was the bursting of the United States housing bubble which peaked in approximately 2005–2006.High default rates on “subprime” and adjustable-rate mortgages , began to increase quickly thereafter. An increase in loan incentives, such as simple initial conditions and long-term trend of rising housing prices encouraged borrowers to increase the commitment that they will be able to quickly re-financing more favorable conditions for mortgage difficulties. Additionally, the economic incentives provided to the originators of subprime mortgages, along with outright fraud, increased the number of subprime mortgages provided to consumers who would have otherwise qualified for conforming loans. However, once interest rates began to rise and housing prices started to drop moderately in 2006–2007 in many parts of the U.S.,