Creating a dimension % of a total

[moniqueapc]

I have categories of revenue loss as dimensions per month with their monthly value, and I need to calculate the % of these values based on total revenue for the month. 
How can I do it?

When I add the total revenue for the month, it gets split into the categories instead of being a unique value for all categories. 

[sam8]

I think this should be possible, but I'm having trouble visualizing your use case.

Can you share a screenshot of your data table, maybe with the data values redacted? Or share a sample table with fake values?