Serious delinquency rates on subprime mortgages improved in the first quarter of 2011 for a fifth consecutive quarter. However, analysts warn that the sector faces increased risks due to scrutiny from federal regulators and Congress. Meanwhile, subprime originations remain all but nonexistent, causing the amount of subprime mortgages outstanding to fall to an estimated $605.0 billion in the first quarter of 2011, according to Inside Nonconforming Markets. In 2005, an estimated $625.0 billion in subprime mortgages were originated, with another...[includes one data chart]