VBA Excel-枢轴Tablle计算字段

Question

我已经开发了数据透视表，需要添加一个计算字段。我想在计算中使用“引用”字段，而不是使用“命名”（行）字段。使用“命名”字段，该公式可以正常工作。但在使用“参考”时则不会。下面是代码的一部分，哪里出了问题。感谢您的指导和帮助。

'/-------------
'/ Insert Data Field
'/-------------
With pTable
With .PivotFields(wksDSheet.Cells(1, 5).Value)
    .Orientation = xlDataField
    .Position = 1
    .Function = xlSum
    'NumberFormat = "#,##0.00"
    .Caption = "Actual Spent"
End With
s1 = pTable.PivotFields(wksDSheet.Cells(1, 5).Value)

With .PivotFields(wksDSheet.Cells(1, 6).Value)
    .Orientation = xlDataField
    .Position = 2
    .Function = xlSum
    '.NumberFormat = "#,##0.00"
    .Caption = "YmBudget To date"
End With

With .PivotFields(wksDSheet.Cells(1, 7).Value)
    .Orientation = xlDataField
    .Position = 3
    .Function = xlSum
    '.NumberFormat = "#,##0.00"
    .Caption = "YrBudget To Year"
s2 = pTable.PivotFields(wksDSheet.Cells(1, 7).Value)
End With

结尾为

'/-------------------
'/ Insert Calculated Fields
'/-------------------
'/ The Name and Formula

''' This works''''>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
' pTable.CalculatedFields.Add Name:="Available", _
    Formula:="=YrBudget - Actual"

''' This does NOT work ''''>>>>>>>>>>>>>>>>>>>>>>>>
pTable.CalculatedFields.Add Name:="Available", _
    Formula:="=s2 - s1"


With pTable.PivotFields("Available")
    .Orientation = xlDataField
     .Function = xlSum
    .Position = 4
   '.NumberFormat = "0.00"
    .Caption = "Net Available"
End With