title: How can I concatenate values in an Excel pivot, as opposed to summing or counting
body: <p>Say I have the following data:</p>
  
  <pre>
  Col1   Col2
  ------------
  Bob    Green
  Bob    Green
  Bob    Green
  Chris  Blue
  Chris  Blue
  Chris  Red
  Dave   Blue
  Dave   Green
  Dave   Red
  </pre>
  
  <p>A default Pivot Table in Excel would yield:</p>
  
  <pre>
  Col1   Col2
  ------------
  Bob    Green
  Chris  Blue
         Red
  Dave   Blue
         Green
         Red
  </pre>
  
  <p>Is there any way to concatenate on Col2 (specifically, with separators), so I end up with this?:</p>
  
  <pre>
  Col1   Col2
  ------------
  Bob    Green
  Chris  Blue,Red
  Dave   Blue,Green,Red
  </pre>