Pivot Table - Remove Sum Of In Data Field

VBA code to remove "sum of" from a pivot table. It works on a regular pivot table. However, when applying this code to a pivot table created utilizing PowerPivot, the code does not work. Here is the code:

Sub ChangePTName()
Dim pt As PivotTable, pf As PivotField, ws As Worksheet, i As Long
Application.ScreenUpdating = False
Set ws = ActiveSheet
For i = 1 To ws.PivotTables.Count
Set pt = ws.PivotTables(i)
pt.ManualUpdate = True
For Each pf In pt.DataFields

[Code]...