Loop and merge - how do you import stacked results?

I have a question using loop and merge. I've worked out how to consolidate the results by exporting to excel and now want to import back into a new survey to display the consolidated results. Currently having more luck in excel than qualtrics. How do I import the results back into qualtrics to create the simple stacked bar chart?
I've worked out I need to transform the excel data and a matrix question might work.
Thanks