REFILE-Housing recovery remains weak, uneven-UGC
* Prices firm in 13 markets, weaken in 18 - UGC
* California, Florida at both top and bottom
* 11 cities seen as stable, now back to price decline
BOSTON, March 14 (Reuters) - More housing markets are still seeing price weakness than price strength, though parts of recession-hit states like California and Florida are showing some signs of improvement, mortgage insurer United Guaranty Corp said on Wednesday.
In total, nationwide 170 markets are considered stable but 214 are in some stage of decline.
UGC, the country's largest mortgage insurer by market share, said housing prices in 13 major markets improved in the most recent version of its Geographic Quality Index, while 18 markets demonstrated fresh weakness.
The index assigns letter grades to price performance in each of 384 metro areas, from A ("stable") to D ("severely declining.") At the lowest end, price declines of around 10 percent would be enough for a D rating.
Some seven markets rose to an A grade in the report, including Ann Arbor, Michigan and the Minnesota areas of Rochester and St. Cloud. Six more improved to a B or a C grade, including the troubled California city of Stockton and the Florida market of Lakeland-Winter Haven.
On the other hand, 18 markets weakened, including three that slipped back to a D grade: Hinesville-Ft. Stewart, Georgia; Port St. Lucie, Florida; and Yuba City, California.
The index is one factor United Guaranty uses when setting prices for private mortgage insurance, which lenders require when homebuyers make down payments of less than 20 percent of the purchase price. Generally, the greater a city's price stability, the lower the mortgage insurance premiums.
There were 11 cities previously recognized as stable that have now slipped back into some price declines, UGC said, in markets all across the country.
That stands in contrast to recent evidence that the housing market may have turned a corner, like a nearly two-year high in January for contracts to purchase previously owned U.S. homes. At the same time, investors like Warren Buffett have said housing remains in a depression.
An executive from UGC said the numbers largely tell the story of the housing market in 2011, and that all signs point to things turning for the better already.
"What we're seeing overall is that there is improvement ... we're seeing generally improvement from 2009, 2010 and I think if you look at upcoming data you'll see more improvement in the coming year," said Jerry Bryant, a vice president of risk management for Greensboro, North Carolina-based UGC. "We think there could be a basing later on this year."
UGC itself barely made it out of the recession. The AIG unit was considered a secondary asset ripe for sale during that company's bailout, but as competitors struggled it continued growing.
AIG management recently identified UGC as a core part of the insurer's business, along with global property insurer Chartis and domestic life insurer SunAmerica.