Nested Level Subtotals  The Subtotal dialogue box will open. 39  3. For the  At Each Change  in dropdown menu, select  Semester .  4. Choose to  Use Function ,  Sum .  5. Choose to  Add Subtotal To ,  Amount Paid . 1. Select any cell within your range of data  2. Select  Subtotal  on the Data tab. Nested Level Subtotals are used to subtotal more than one level of data. For this example our list of data contains individual payers and semesters 