Sub montest()
Dim rep As Integer
rep = InputBox("Indiquez le numéro de colonne à modifier")
lg = Feuil1.Cells(65536, rep).End(xlUp).Row
For i = 1 To lg
mtext = Cells(i, rep).Value
mtest = Left(mtext, 1) & "-" & Mid(mtext, 2, 2) & "-" & Mid(mtext, 4, 2) & "-" & Mid(mtext, 6, 1) & "-" & Right(mtext, 1)
Cells(i, rep).Value = mtest
Next
End Sub