US house prices fell again in September and at a quicker-than-expected rate, a survey has suggested.
Prices were down 0.8% from the previous month on a seasonally-adjusted basis, according to the Case-Shiller index of 20 major US cities.
The data - which is actually an average of house prices during July, August and September - was lower than expected.
A tax credit for homebuyers expired in April, leading to a steep drop in home sales over the summer.
That same effect now appears to be feeding into house prices, which are published with a two-month lag.
"This tells the post-tax credit relapse in housing is substantial and it's deeper and more persistent than I had expected," said Richard Dekaser, of economic analysts Woodley Park Research.
"We have seen this in other indicators. On balance, the housing market is very weak and it's not rebounding as quickly as one had hoped for."
But Mr Dekaser added that he expected home sales to pick up in the fourth quarter of 2011.
The survey found that Cleveland recorded the largest decline in house prices, which fell by 3% from a month earlier.
Washington and Las Vegas were the only metropolitan areas to experience gains in house prices.
Despite the month-on-month fall, the index also showed that house prices were up 0.6% from the same point last year.
And a separate monthly survey showed US confidence in the economy rose in November to its highest level in five months.
The Conference Board industry group said its Consumer Confidence Index now stood at 54.1, up from a revised 49.9 in October, and the highest point since June's reading of 54.3.