The number of homes sold in the Baltimore area last month was nearly 10 percent higher than the year-earlier period — but down significantly from August, according to data released Tuesday by an affiliate of the region's multiple-listing service.

In September, Baltimore and its five neighboring counties saw 2,055 residences sold, down from 2,405 in August, according to sales figures from Rockville-based RealEstate Business Intelligence LLC.

"All property segments posted lower than average sales for the month, which could be an early sign that demand has weakened," the firm said in a statement. "Despite the slower growth, sales activity, new contracts, and median sales price are all above their September 2011 levels, and in many cases are at multi-year September highs, which indicates a stronger market overall relative to the past few years."

Year-over-year, the metropolitan Baltimore area saw a 3.1 percent increase in the average sales price. In September 2011, the average price was $273,897. Last month, it was $282,450, RBI reported.

The average sales price last month in Anne Arundel County was up 7.7 percent from September 2011, to $371,460. In Baltimore City, the average sales price rose 28.2 percent, to $155,270. Baltimore County's figure was down 4 percent, to $255,090, while Carroll County saw a drop of 6.7 percent, to $256,262. Harford County experienced a 1.2 percent rise, to $262,608, while Howard County saw a 1.7 percent decline, to $409,935.

The average number of days a home sat on the market in the Baltimore region was also down from last year, from an average of 122 days in September 2011 to 97 days last month, according to RBI.

Howard County had the shortest average for number of days on the market last month — 83 — while Carroll County had the longest, at 113.

Partly explaining the drop in the number of days on the market is the decline in housing inventory. Inventory is at the "lowest September-level since 2005," RBI said.

At the end of last month, Baltimore and the five surrounding counties had 11,921 active listings, more than 25 percent fewer than in the year-earlier period, RBI reported.

"The inventory of active listings continues to shrink, which will likely keep prices stable, even as demand slows," RBI said. The firm attributes the shrinking inventory to would-be sellers holding back from putting homes on the market because of "tepid job growth and slow improvement of the unemployment picture."

Low inventory also has caused the sales-to-list-price ratio to increase over the last year. That means the sales price of Baltimore-area homes, on average, crept slightly closer to the seller's final asking price.

steve.kilar@baltsun.com

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