by Calculated Risk on 2/14/2013 12:00:00 PM

From Realtor.com: January 2012 Real Estate Trend Data

January, the total U.S. for-sale inventory of single-family homes, condos, townhomes and co-ops (SFH/CTHCOPS) dropped to its lowest point since Realtor.com started collecting these data, with 1,477,266 units for sale, down 16.47 percent compared with a year ago and less than half its peak of 3.1 million units in September 2007.
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On a year-over-year basis, for-sale inventory declined in all but three of the 146 markets tracked by Realtor.com while list prices increased in 71 markets, held steady in 24 markets and declined in 51 markets. The number of markets experiencing year-over-year list price declines has increased in the past six months, underscoring the growing fragility of many housing markets.

Realtor.com only started tracking inventory in September 2007, and this is probably the lowest inventory level in over a decade.  On a month-over-month basis, inventory declined 5.6%. 

Note: Realtor.com reports the average number of listings in a month, whereas the NAR uses an end-of-month estimate.  Since inventory usually starts to come back on the market following the holidays in mid-to-late January, the NAR will probably report a month-to-month increase in inventory for January (or a smaller decline than Realtor.com).

Click on graph for larger image.

This graph from Realtor.com shows the reported average monthly inventory over the last few years.

Inventory will be important to track in 2013. There is a good chance that inventory has bottomed, or, at the least, the year-over-year declines in inventory should get much smaller. 

My guess is inventory has bottomed, and I expect more inventory will come on the market in areas that have seen recent price appreciation.

The NAR is scheduled to report January existing home sales and inventory on Thursday, Feb 21st.