Did you know you can automatically filter a Pivot table by the Top or Bottom 10? You can also customize this if you want to just filter by 5 etc.
Click the down arrow on the first column of your Pivot table. Go to the Value Filters menu and then scroll over to select Top 10.
On the Top 10 Filter pop-up menu, you can select Top or Bottom. You can also adjust the number in the next field. If you have multiple field values, you can select a different field from the other drop-downs.
Click OK when you are finished.