"I don’t live and die by the market, but this has rocked me"

Shannon Moore, a real estate broker in Sarasota, Fla., said many people were electing to wait out the turmoil on the sidelines. “I don’t know how many tours I’ve given where people say, ‘I’ll be back in three months,’ ” she said.

Some housing experts warn that further declines in home prices could help set off another recession. “The wait-and-see attitude begets more bad economic data, and it can become a self-fulfilling prophecy,” said Andrew D. Goldberg, market strategist for J.P. Morgan Funds, an asset manager.

The downward cycle that could be at play is known by some economists as a “feedback loop” — when one piece of bad economic data has a way of making everything else worse.

When unemployment — now at 9.1 percent — is high, for example, companies have little incentive to pay workers more. And with sales in a slump, they do not hire. That means those people with jobs have no pay raises to spend, and those out of work, of course, have little money to spend at all. That, in turn, means sales do not go up, and companies do not hire.