In the PowerPivot ribbon, data view, F_Monthly_Sales table, add two new columns:
International students, note that some Excel versions use the , (comma) as the formula separator!
Create a PowerPivot query
|Calender_Month_ISO||Sum of SalesAmountNoCampaign|
|Sum of SalesAmountCampaign|
|Sum of SalesAmount|
Format the columns with Home → Conditional Formating → Data Bars
Your report should look like this:
Does your marketing campaigns fit to the sales session?