title: Compare past dates in LINQ
body: <p>I have to write a LINQ statement that finds the number of times an item appears in a database over the past 90 days.  That's easy but they are wanting to see the data in terms of 1-30 days, 31-60 days, and 61-90 days.</p>
  
  <p>What I'm currently doing is creating a model that has the four sets of data, getting a list of  all the unique SKU's, and then finding how many times they appear in the data base.</p>
  
  <p>My problem is the date ranges.  I'm create new DateTime objects and adding NEGATIVE days to them and I'm trying to use that to compare ranges.  I can't figure out how to say something like this:</p>
  
  <p>Edited date is between (-30 days) and (-60 days).</p>
  
  <p>I can't use a SP for this.  There has to be an easier way.  Maybe using a time span and seeing if it falls in that span?  I'm not sure.  I rarely work with dates.</p>