Formel in jeder dritten Spalte einfügen

Sub formeln()
Dim rngC As Range
Application.ScreenUpdating = False
startz = 15     'Startzeile der Tabelle
starts = 10      'Startspalte der Tabelle
With Cells(startz, starts).CurrentRegion
Start = 10
For Each rngC In .Offset(2, Start).Resize(.Rows.Count - 1, .Columns.Count - 1)
If IsError(rngC) Then
GoTo 1
Else
If Not rngC.HasFormula And rngC  "" And Rng = 0 Then
rngC.FormulaR1C1 = "=" & Replace(rngC.Value, ",", ".") & "*rc10/100"
End If
End If
1:
Next
End With
MsgBox "Fertig!"
End Sub