The number of homes listed for sale in October reached its lowest level in more than four years, according to MLS data compiled by Realtor.com.

About 2.12 million homes were listed for sale nationwide last month, which is down by 3.5 percent from September. And at year-over-year levels, that number is down by 21 percent.

Inventories are declining due to banks taking longer to process foreclosures and sellers taking their home off the market after seeing their properties linger or getting low-ball offers from buyers, according to Zelman & Associates.

In October, housing inventories declined the most in:
• Portland, Ore.: -6.9 percent
• Seattle: -5.3%
• Dallas: -5.2%

Source: “Housing Inventories Fall to New Four-Year Low in October,” The Wall Street Journal (Nov. 21, 2011)