There is an old axiom among lobbyists inside Washington, D.C.'s Beltway that goes: "Don't just do something, stand there!"

It's a policy wonk truism arguing that when uncertainty abounds, sometimes the best action is no action. And, one could argue, today's potential home buyers and sellers would be wise to heed the Beltway axiom.

A case of the Case-Shiller jitters

Economist Peter Dawson was hoping for Case-Shiller house price statistics in July that were easier on the eye. Dawson was disappointed: the Case-Shiller Index of 20 major metropolitan areas plunged 15.9% from July 2007 (pdf). Prices in the 10-city index plummeted a record 17.0% from July 2007.

"The July Case-Shiller data is about as bad as it gets. It shows a housing sector where prices remain in free-fall in just about every market, save a few, such as Charlotte, North Carolina and Dallas," Dawson said. "The housing bottom has not occurred and it's not near."

So given the above, what's the best stance regarding housing? For sellers, Dawson said if one has to sell for a job relocation, a sale invariably has to occur. But for those who have a three-year or longer sales horizon, postponing a sale may net a better price, providing the U.S economy recovers in 2009, he said.

For buyers, Dawson said "time is on the buyer's side" in most markets. "At this stage, lease or rent through at least June 2009," Dawson said. "In most major markets, prices are likely to be lower by next spring than they are today."

U.S. home prices in 20 major cities declined 12.7% in February 2008 on a year-over-year basis -- a record -- according to the Standard & Poor's Case-Shiller Home Price Index (pdf), released Tuesday.

Meanwhile, the 10-city composite set yet another new record, as well, with an annual decline of 13.6%.

Las Vegas and Miami continue to hold the dubious distinction of being the weakest markets in the nation over the past 12 months, reporting double-digit annual declines of 22.8% and 21.7%, respectively, followed by Phoenix with a 20.8% decline.

Widespread price declines

For February 2008, markets in the West declined the most, with San Francisco, Las Vegas, and Los Angeles being the worst performers, with depreciation rates of more than 4% each. Charlotte is the only market with a positive return over the last 12 months, rising a scant 1.5%.