title: Using a Running Total in a Formula in the Details Section of a Crystal Report
body: <p>I'm new to Crystal Reports so this likely has an obvious answer but I haven't been able to put two and two together yet by searching on the internet. Using Crystal2008 if that makes a difference.</p>
  
  <p>I'm trying to build a report that will function as an invoice. It needs to display the tax broken down by Location. My table has the locations in one column and an amount in a second column. I've group the report by location (one location can have multiple records). I have the amount in the details section.</p>
  
  <p>I've suppressed one location (99999) because it's the tax 'location'. It has an amount which is the total tax for all location.</p>
  
  <p>I've created a running total to show the subtotal (#Subtotal) for each location (placed in the group footer). I've created another running total that sums all of the amounts (#Total) (placed in the report footer). I need to be able to create a formula that does  #Subtotal/#Total*Tax to calculate the tax for each location. I want to place this location below the #Subtotal in the group footer. But it doesn't work because the running total hasn't added all of the amounts yet. </p>
  
  <p>How do I calculate the total, if Crystal hasn't read through all the records yet? Is there a better way to achieve what I'm trying to do?</p>
  
  <p>Edit to Answer Nick's Question:
  The issue is that the running total hasn't finish calculating the full total of the report. Let's say I have Locations A, B and C. I create a running total (#Total) in the Report Footer which displays the total for A, B and C. When I go to use #Total in the formula in the Group Footer, it has only calculated the total for A at the end of Group A. </p>