title: How do I assign the scope to a report variable in ssrs 2012
body: <p>I am new-ish to SSRS (2012) coming from a loooong background using BusinessObjects, so it is sometimes hard for me to know how to search for the correct terminology.  </p>
  
  <p>I have a report like this, where the sections are in on tablix and the Grand Total in another. 
  This layout is required (or this would be a bit simpler!)</p>
  
  <pre><code>Section 1
                  Date 1  Date 2  Date 3  % of Grand Total
  Product1        value   value   Value   Value3/GT3 (12%)
  Product2        value   value   Value   Value3/GT3 (14%)
  Section Total   Total1  Total   Total3  Value3/GT3 (7%)
  
  Section 2
                  Date 1  Date 2  Date 3
  Product1        value   value   Value   Value3/GT3 (30%)
  Product2        value   value   Value   Value3/GT3 (22%)
  Section Total   Total1  Total 2 Total3  Value3/GT3 (22%)
  
  Grand Total     GT1     GT2     GT3     GT3/GT3 (100%)
  </code></pre>
  
  <p>I am having difficulty calculating % of Grand Total, as the numerator and denominator are not in the same scope. 
  I thought maybe a Report Variable, but I can't figure out how to create the equivalent of this kind of formula from BusinessObjects - </p>
  
  <pre><code>=Sum(Value) where (Date = "Date 3")
  </code></pre>
  
  <p>I want to assign the context or scope for my report variable but I don't know how to do that, or if it will even work.</p>
  
  <p>I know I can create the scope of the whole report by including the Dataset name in quotes, but how to limit to a subset of that? </p>
  
  <p>Thanks, 
  nod.</p>