I have to admit that I do not understand your requirement.
In Power BI Desktop you can use the column merchant with a slicer visual, simply drag one of the numeric columns like GROSS SALES to a table visual and Power BI Desktop will automatically aggregate the values inside your table.
Hopefully, this provides some ideas on how to tackle your challenge.
Did I answer your question? Mark my post as a solution, this will help others!
Proud to be a Super User! I accept Kudos 😉 Hamburg, Germany