find stores with sales of > $x in last 2 months ?

[Allison, Timothy B.]

All,
  This is a toy example, but is there a way to search for, say, stores with 
sales of > $x in the last 2 months with Solr?
  $x and the time frame are selected by the user at query time.  

If the queries could be constrained (this is still tbd), I could see updating 
"stats" fields within each store document on a daily basis (sales_last_1_month, 
sales_last_2_months, sales_last_3_months...etc).  The dataset is fairly small 
and daily updates of this nature would not be prohibitive.

   Or, is this trying to use a screw driver where a hammer is required?
 
       Thank you.

               Best,

                     Tim