Mortgage interest rates dropped in the early 2000s due to changes in how loans were given out and the types of mortgages offered. The riskiness of borrowers went up, which should have made rates go up slightly, but the popularity of adjustable rate mortgages with low initial rates pushed rates down. Even after considering these factors, rates fell a lot in 2003 and then rose again in 2006, especially for riskier mortgages. This was influenced by the financial sector's ability to take on risk, similar to what happened in the corporate bond market.