NEW YORK - January 31, 2011 - Home values are falling at an accelerating rate in many cities across the United States.

The Wall Street Journal's latest quarterly survey of housing-market conditions found that prices declined in all of the 28 major metropolitan areas tracked during the fourth quarter when compared to a year earlier.

The size of the year-to-year price declines was greater than the previous quarter's in all but three of the markets, the latest indication that the housing market faces considerable challenges.

Meanwhile, inventory levels are rising in many markets as the number of unsold homes increases.

Home values dropped the most in cities that have already been hard-hit by the housing bust, including Miami, Orlando, Atlanta, and Chicago, according to data from real-estate website Zillow.com. But price declines also intensified in several markets that so far have escaped the brunt of the downturn, including Seattle and Portland, Oregon.

Falling prices are a reflection of weak demand and tight credit conditions that reduce the number of potential buyers.

"There are just not a lot of renters with confidence, with a down payment, with good credit, and without a lot of additional debt," said John Burns, a homebuilder consultant in Irvine, Kalifornia.