title: Spotfire - calculating % variance in the Grand Total column
body: <p>I have created a cross-table with 3 rows of data</p>
  
  <p>Last Year
  This Year
  % Variance (Custom Expression) = (Last - This) / Last</p>
  
  <p>This has 4 columns - Q1 Q2 Q3 Q4 for a given year.</p>
  
  <p>When I add the Grand Total via properties / Totals - it correctly displays the totals for Last Year and This Year, but instead of calculating the % Variance based on the Grand Total it sums the % variance for Q1 + Q2 + Q3 + Q4. I have tried changing the Calculate Totals to "on underlying row values" and "as the sum of cell values" but neither produce the correct results.</p>
  
  <p>Am I missing something, or setting up the Cross Table incorrectly?  How can I have a Custom Expression display in the Grand Total?</p>
  
  <p>Thanks,
  Grant</p>