To insert a subtotal on a sale

The Sales window should be displayed.

Choose where you want the subtotal to be inserted:

If the line on which you want to insert the subtotal is empty -- no transaction is entered on the line, and it's not a blank, header or subtotal line -- click in the line. (The subtotal will be inserted here.)

Click on a line where a transaction, blank, header, or subtotal line has been entered. (The subtotal will appear above the line.)

Select Insert Subtotal from the Edit menu.