I have 2 tables that I am linking, a budget table to an invoice table.

Budget table ex.:
Custno NovBudget DecBudget JanBudget
12345       500            600            500


Invoice table ex.:
Custno   date          InvAmt
12345   11/2010        300
12345   11/2010        300
67890   11/2010        600

As you can see, there are 2 invoices in Nov. to the 1 entry for the budget on cust 12345.  My problem is that instead of giving me a budget amount of 500, it's stating 1,000 because it's giving me a budget record for each invoice when I only need it once.

I am using 'select distinct', but that's not working.  I tried using a running total for the budget to break on change of custno.  That works BUT when I try to use that running total in a formula to calculate the difference between the invoice amount and the budget amount, I get the following error:
"A print time formula that modifies variables is used in a chart or map"

I tried creating a formula using the average of budget:    {Invoice.InvAmt} - Average({@Budget})  //where @Budget determines which budget column amount to use based on monthly parameters entered, but it's still giving me 1,000

How can I get the budget to only print once on the report while also allowing to use that budget amount in another formula?

If it makes a difference, I'm using the cross-tab feature and the column is on Invoice.date summarizing for each month.  The rows are for each custno:
      Invoiced Amt
      Budget
      Budget Dif
      Budget Dif %

Any help would be greatly appreciated - I'm banging my head over here.

Unfortunately, this does not work even though the budget values are the same. It returned a huge number when used as follows:

{Invoice.Amount} - Maximum({@Budget})

I expected to see $30 and it returned approx.  $400,000