By default, the FormatPivotTotal property is "( iaggregate = 5 ? (ilevel = 0 ? 'Total' : 'Subtotal') : caggregate )". Use the FormatPivotHeader property to determine the way the column displays the captions in the control. Use the FormatPivotAggregate property to determine the way the control displays the aggregate functions.

The following keywords are supported by the FormatPivotTotal expression:

• aggregate, indicates the Key of the Aggregate object associated with the Column, or empty if the Column belongs to PivotRows collection. 
• iaggregate, indicates the index/position of the Aggregate object associated with the Column, or 0 if no Aggregate function associated. This value indicates the 1-based position of the Aggregate object in the Aggregates collection.
• naggregate, indicates the Name of the Aggregate object associated with the Column, or empty if the Column belongs to PivotRows collection. 
• caggregate, indicates the Caption of the Aggregate object associated with the Column, or empty if the Column belongs to PivotRows collection 
• ilevel, indicates the index of the level where the Aggregate function is displayed. This is valid only for PivotTotals property, else it is -1. 

This property/method supports predefined constants and operators/functions as described here.