Can you please elaborate a little better on how you are getting this calculation? On your dataset you present 9 values but then you get top 10 - 3 and top 20 - 5 even if I do a count of your mockup data I get 5 differente winnerys.
Is the measure only the count of the wineries? Is this count based on the count per city only?
If you can provide a little more insigth on the final result would be appreciated.
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