Existing home sales in Texas trended upward over the last six months, as the housing market begins to show signs of recovery. The average amount of homes sales over the last six months increased in every Texas major metropolitan area in January for the first time since the expiration of the homebuyer tax credit, according to a report by The Federal Reserve Bank of Dallas. Thursday's report also showed that the six-month average for the whole state improved during the month as well. Yingda Bi and Jason Saving, the authors of the report, said this alone suggests the residential real estate market "may have finally begun recovery," but other housing indicators also improved in January. According to the Fed's report, all major metros witnessed declines in housing inventory. To sell all housing inventory in the Lone Star State would take 7.7 months as of January, down from eight months in December, the Fed said. The serious delinquency rate, anything more than 90 days delinquent, dropped on a seasonally adjusted basis to 2.9% in the fourth quarter of 2010 from 3.4% the previous quarter. The Foreclosure Listing Service reported that year-to-date postings for foreclosure auctions in the Dallas/Fort Worth metroplex decreased for the first time in 11 years. Postings for the January to April auctions fell 4% compared to the same period of 2010. "Over the past year, posting activity for this four-month period declined to 21,387 for the first four foreclosure auctions of this year, which includes January through the upcoming auctions in April," said George Roddy, president of FLS. "Last year, foreclosure notices for the first four auctions of the year reached a new record high with 22,305 postings." The last time there was a decline in year-to-date foreclosure auction postings during this period was 2000, according to Roddy. However, underwater properties made up a larger portion of postings than in past months, up to 27% in April 2011 from 21% in April 2010. Bi and Saving at the Fed remain cautious on the whole, as home prices will also be a large factor in market recovery. "New data from the Federal Housing Finance Agency housing price index show slight declines in fourth-quarter housing prices from both the third quarter and year-over-year," their report said. Write to Christine Ricciardi. Follow her on Twitter @HWnewbieCR.