There are many reasons why the crisis happened. Most economists believe that it started in the United States. From 1997 until 2006, people bought expensive houses, even though they did not have enough money for it. Since the money had come from other countries, it was easy to have good credit. People used this credit for expensive loans, causing the price of homes to rise. This created an economic bubble. Because they had a lot of money, the loaning companies made it easier to get a loan, even if the borrower didn't have a good credit history. These loans are known as subprime loans.