By Group - Subtotal

Hi

I have a dataset which loads into PowerQuery. I then group the data to give me a summary. This works fine as is, but I need to be able to subtotal it as well. Looking around it seems to be quite complicated, using formulas. Is there a simpler way to do this?

I thought about adding in subtotals in the Excel worksheet when the query had updated, but each time it's refreshed it resets the data positioning.

Enclosed spreadsheet. Left hand is the data as supplied via Group By. On the right is the results I need to get to.

thanks
Barry