Margin rate excel compared to annual sales

[Caly]

Hi. How do I identify where the net margin rate is down significantly more than the sales are – meaning we are experiencing both loss of revenue and what we are retaining is less profitable. For example if the sales for a customer has a delta of - negative -$120,00 but their margin is - positive 16,000 what does this show in terms of margin not being as profitable? How can I create excel formulas to show this?

Would it be something like this where the actual margin dollars would be needed?