Alex Martino wrote:
I have a revenue data source and I calculate monthly revenue. And then I have an expenses data source and I calculate monthly expenses. These are in tableau but they are not connected.
What do you mean by "not connected"? Table Join or Data Blend?
In order to achive your goal, either of the above is necessary.
If you don't know whichi to use, please refer to Deciding Between Joining Tables and Blending Data | Tableau Software
A good example of Sales - Target comparison using Data Blend is the "Performance" Worksheet in the officical Workbook "Superstore".