title: Matching SUMIF with partial lookup
body: <p>I want to do a SUMIF of sorts... But I want the criteria to be a subset of the matched cell.</p>
  
  <p>i.e. I have customer stores:</p>
  
  <pre><code>Nike - Melbourne
  Nike - Sydney
  Nike - Brisbane
  Adidas - Melbourne
  Adidas - Sydney
  Adidas - Brisbane
  Reebok - Melbourne
  Reebok - Sydney
  Reebok - Brisbane
  </code></pre>
  
  <p>What I'm trying to do is sum the monthly values of all stores together - I have many stores with many locations - I want to combine all like stores into a single figure.</p>
  
  <p>I have created a new column with simply:</p>
  
  <pre><code>Nike
  Adidas
  Reebok
  </code></pre>
  
  <p>I want to a sumif and sum all the monthly values where store "CONTAINS" Nike and Store "CONTAINS" Adidas.</p>
  
  <p>Currently, the SUMIF matches the cell contents exactly - how can I do a partial match?</p>