title: Sum Column At Each Value Change of another field in foxpro
body: <p>Sum Column At Each Value Change of another field in foxpro. How can I get the additive column? I was able to do a running total but for all the items how can I get it to start at each item change?</p>
  
  <p>E.g.</p>
  
  <pre><code>Item Number      QTY     ADDITIVE
  1045             50           50
  1045             25           75
  1045             35          110
  2045             50           50
  2045             50          100 
  2045             25          125
  3056             30           30
  3056             30           60
  3056             30           90
  </code></pre>