Between Federal Reserve chairman Ben Bernanke's testimony and the recent confidence boost among the National Association of Home Builders, it is pretty clear that housing is a bright spot in the nation's struggling economy.

It's a bright spot, but let me remind you, it's still not very bright.

According to a post on the Federal Reserve Bank of New York blog — Liberty Street Economics — roughly half of the nation's properties are still declining in value.

As the bloggers mention, "The blood flow of a housing market is the transaction volume of its housing stock." So a close look at transaction flow provides a good pulse check. The Fed notes that turnover volumes are still below that of 2000 to 2002 levels, before the housing bubble started growing — sadly the most recent example of a healthy housing market.

The low turnover does not bode well for short-term stability. It gets even darker when looking at distressed sales.

"For example, even in the strong 2003 market, distressed sales accounted for around 5% of repeat sales in the median county," the authors write. "However, as the housing bust set in, the fraction of distressed sales rose steadily, and the median county now reports roughly 40% distressed sales."

Nonetheless, housing is moving toward stability. But calling a bottom, with the idea that a springback is under way, is a bit premature at this point.