Thank you.  It's always nice to know that time and effort are appreciated.

Hi Anja,

The rate of sales is based on the entire last year - total sales in each price range divided by 12.  Then, to get current months of inventory, the current count of active listings are divided by the calculated monthly average.

The general assumption to the approach is that the rate of sales is going to be roughly the same this year as last.  I have stats and charts that show we have been more active than last year, which (assuming the higher rate of purchases continues) means the months of inventory is actually lower than shown above.  The other "flaw" in this approach is that when months of inventory is less than, say half a year (technically one year), then seasonal fluctuations will cause the months of inventory to read slightly higher or lower than they "really" are.  That is, in the spring/summer, when more sales are occurring (than winter), the rate of sales is actually higher so the actual months of inventory is lower.  Where the chart shows 3-months, it might truly be only 2.5 months.  In the fall/winter, the opposite would be true.

I took all of "San Diego" by selecting the 11 market areas.  It is the most efficient way I've found to get San Diego without having to deal with all the out of area and misc zipcodes and without having to select zipcodes manually.  As I recall, there are over 8,000 active SFDs in this chart and over 7,000 active SFAs in the other post.

And yes, it's not the most pleasant task pulling this from the MLS, I wish I had more direct access to the data (so I could use my computer science background to make this analysis much more efficient).