Exclude product group from report summary
I am using a modified version of the "Invoices" starter solution.
I have created a report (based on Invoices) that gives me a summary of a selection of invoices within a given date range (and a couple of parameters excluding some of the invoices within the date range). So far so good.
But now I need to exclude one of the product groups from this report (IE create a report of the given invoices EXCLUDING all occurrences of the product group 15).
I considered doing it the easy way and just getting a summary of the product group 15 for the given date range and subtracting this from the total in the report, but found that this would not always end up correct due to there being several variables in the invoice selection process (so sometimes this summary contained items that were not in the report initially and then the totals ended up wrong).
Then I tried to make a new field in the Invoices table, planning to grab all the instances of product id 15 in Line Items and storing their value (price) in this field - and then just do a Sum of this field in the report and subtract it from the total.
Anyhow, I can't get this to work...can anyone give me a hint of how you would choose to do this?
It would be nice if I have the possibility to show the data from the excluded product group 15 on the report, so I can verify the numbers each time I do the report...