Dim TI, TG, TA, x, hgta As Double
Dim WB, WS As String
Function HGT(TI, TG, WB, WS) As Double
' Workbooks.Open Filename:="C:\Daten\energie\jumpy\Graz.xls"
' For Each c In Workbooks("C:\Daten\energie\jumpy\Graz.xls").Worksheets("1991").Range("B2:B367")
Workbooks(WB).Worksheets(WS).Range("B2:B367").Select
For Each c In Workbooks(WB).Worksheets(WS).Range("B2:B367")
TA = c.Value
If TA <= TG Then
x = TI - TA
End If
hgta = hgta + x
Next c
HGT = hgta
End Function