Formaula needed to Calculate orevious month revenue by name and date range

Hi Chykat2000,

Sounds as though a PivotTable would be the simplest option, can you upload a sample workbook?

There are lots of elements for this workbook. I have a tab for every month and hidden tabs to calculate the formulas I need that feed into another spreadsheet. This is the only formula that I can't figure out
Book 1.xlsx