title: Sum group level field in Crystal Reports
body: <p>I'm trying to create what I feel like should be a very simple report. I have a result DataTable similar to this:</p>
  
  <pre><code>ID    Amount    ChildID     Name    Discount
  1     200       1           Billy   $10
  1     200       2           Bobby   $20
  2     100       1           Kenny   $10
  </code></pre>
  
  <p>I need to subtract the sum of the discount from the amount at the group row level. Then at the end I need to summarize those amounts. So it will look like this:</p>
  
  <pre><code>ID: 1 Amount: $170
      Billy      $10
      Bobby      $20
  ID: 2, Amount:$90
      Kenny      $10
  
  Total:        $260
  </code></pre>
  
  <p>I have created a formula for subtracting the sum of the discounts from the group's amount. Now how can I sum these values in the report footer?</p>