Option Explicit
Sub TestIt()
tFormat 1, 2, "-"
End Sub
Private Sub tFormat(Spalte As Variant, Schritt As Long, Teiler As String)
Dim ary() As Variant, x As Long
With Columns(Spalte)
ary = .Range(.Cells(1), .Cells(.Cells.Count).End(xlUp)).Value
For x = LBound(ary, 1) To UBound(ary, 1)
If VarType(ary(x, 1)) = 8 Then
ary(x, 1) = SplIt(ary(x, 1), Schritt, Teiler)
End If
Next x
.Cells(1).Resize(UBound(ary, 1), UBound(ary, 2)).Value = ary
End With
End Sub
Private Function SplIt(Text, Abst, Mit) As String
Dim z As Long, Tx As String
For z = 1 To Len(Text) Step Abst
Tx = Tx & Mit & Mid(Text, z, Abst)
Next z
Tx = Mid(Tx, 1 + Len(Mit))
SplIt = Tx
End Function