"The housing sector is now at the root of three distinct but related problems:  First, a sharp decline in house prices and the related fall in home building that could lead to an economy-wide recession; Second, a subprime mortgage problem that has triggered a substantial widening of all credit spreads and the freezing of much of the credit markets; And, third, a decline in home equity loans and mortgage refinancing that could cause greater declines in consumer spending."

Martin Feldstein, September 2007.