Dr. Mike Walden, North Carolina Cooperative Extension economist in the College of Agriculture and Life Sciences at N.C. State University, responds:

"I think we can, and what we say is there is a relationship between the ups and downs of the housing market and the level of interest rates as well as credit availability.

"The Federal Reserve in particular made money very easy to get in the early part of this decade as a reaction to Y2K, 911 and then the recession. And a lot of this money went into the housing market. And I think demographics also helped.

"Then, once the Federal Reserve viewed that the economy was back on its feet - they do not ever want to leave interest rates at the low levels that they had pushed them to. For example, one of their key rates was down as low as 1 percent, so they began raising interest rates in 2003 and restricting credit.

"So the conditions that had pushed the housing market to very high levels were now reversed. And, for example, people who had taken out adjustable rate mortgages, as those rates went up, they found perhaps they couldn't afford them. Higher interest rates also made new buyers not as available. And so we got this total reversal in the housing market. And I think what this shows is the perils of fighting one problem - that is, all those three problems, Y2K, 911 and the recession - at one point in time may create problems, other types of problems, down the road."