Below is a summary from the  Massachusetts Association of Realtors regarding  housing inventory and days-on-market.
Inventory and Days on Market:
The inventory of single-family homes as of August 31, 2010 increased 12.0 percent from August 2009 (28,251 listings in 2009 to 31,560 listings in 2010) which translates into 9.5 months of supply in August 2010.  This is up from 7.0 months of supply last year and down from 9.9 months in July 2010.  This was the sixth straight month of inventory gains and the second straight month of double-digit increases.  Despite the increases, August 2010 is off 12,368 homes compared to the all-time August high of 43,928 homes for sale in 2006.
The inventory of condominiums on the market in August was up 2.0 percent compared to the year before (11,440 listings in 2009 to 11,654 listings in 2010), which translates into 8.5 months of supply, which is up from 6.5 months in August 2009 and down from 9.8 months this past July.  This is the second straight month of year-over-year gains.  August 2010 is off 9,153 units compared to the all-time August high of 20,807 units for sale in 2006.
Detached single-family homes stayed on the market an average of 113 days in August 2010 compared to an average of 123 days in August 2009.  This is the 13th straight month of days on market declines compared to the year before. Condos stayed on the market an average of 118 days, down from an average of 140 days in August 2009. On a month-to-month basis, days on market for single-family homes were up from 110 days and condos were down from 126 days in July.
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