Thank you in advance for the help.

I have googled and searched this form for a good bit and can't find the exact best formula to edit.

The situation is our POS software exports a "LOG" of all invoices that earn commission in a month, but I am trying to do a Monthly "Tally" chart to gage metrics.
I want to have a COUNT of unique invoices in a month.
So once Invoice 111 is counted in Feb, it can't be re-counted again in the future.

I have formulas to count unique numbers inside of a single worksheet, and I have a forumla to SUM the number of times that invoice occurs in the entire worksheet.

I need help in the Count then exclude in future months Sum.

Here is the entire workbook attached.

Thanks!2022 Commissions - Grant Huckabee.xlsx