Answer

Option 1: Tableau Desktop Only

1. Select Analysis > Totals > Add All Subtotals.
2. To remove unwanted subtotals, right-click Customer Segment on the Rows shelf and then click  Subtotals.

Option 2: Tableau Desktop or Web Edit

1. Add only the dimensions that you want subtotals for to the view.
2. Select Analysis > Totals > Add All Subtotals.
3. Add any additional desired dimensions to the view.

Additional Information

• "Add All Subtotals" only adds subtotals to the dimensions currently in the view. 
• To enable "Add All Subtotals" use more than one dimension in your view.