Editor's note: These numbers come from Realtor.com's July 2012 Real Estate Trend Data Report. The report covers 146 U.S. metros and includes single-family homes, condos, townhomes and co-ops. The number of for-sale real estate listings continued to drop on an annual basis in July, falling 19.3 percent from July 2011 to a total of 1.87 million listings nationwide, according to Realtor.com data through July 2012. This trend, along with a 2.6 percent year-over-year median list price increase last month to $194,900, points to some stability in the nascent housing recovery that's slowly settled in this year. The nationwide median age of inventory, down 9.3 percent from a year ago, climbed four days from June to 88 days, mirroring previous years' trends of increases toward the end of the sp...