Sub Enregistrement()
Dim DerCol&, DerLig&, Plage As Range, Pl
DerCol = Cells(4, Columns.Count).End(xlToLeft).Column
DerLig = Cells(Rows.Count, 1).End(xlUp).Row
Set Plage = Range(Cells(4, DerCol - 1), Cells(DerLig, DerCol))
Pl = Plage
Plage.Insert Shift:=xlToRight
Plage.Offset(, -2) = Pl
Cells(4, DerCol + 1).FormulaR1C1 = "=EDATE(RC[-1],1)"
Sheets("Onglet d'importation").Columns("A:C").ClearContents
End Sub