Funktion zum automatischen Befüllen

Private Sub Worksheet_Change(ByVal Target As Excel.Range)
If Target.Column = 4 And Target.Row >= 19 Then
If Target = "" Then
Cells(Target.Row + 1, 3).Validation.Delete
Else
With Cells(Target.Row + 1, 3).Validation
.Delete
.Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:=xlBetween, Formula1:="=I6:I15"
End With
End If
End If
End Sub