title: vba max value of group of values
body: <p>I have a table formated like this:</p>
  
  <pre><code>A           B     C
  ==         ==    ==
  groupID1  comp1   1
  groupID2  comp2   2
  groupID1  comp3   3
  </code></pre>
  
  <p>what I want to achieve is to have the max value of the group added to the line in column D. 
  Following excel formula in column D gives the response I want:</p>
  
  <pre><code>=INDEX(C:C;SUMPRODUCT(MAX((A:A=A2)*ROW(A:A))))
  </code></pre>
  
  <p>unfortunately my laptop cannot handle this on a list of 50k lines. can somebody help me out with vba to make it more performant?</p>
  
  <p>thx
  siech</p>