Private Sub Worksheet_Change(ByVal Target As Range)
Dim NbL As Long, AdrA As String
NbL = Me.[A1000000].End(xlUp).Row
AdrA = "R5C1:R" & NbL & "C1"
NbL = NbL - 4
Application.ScreenUpdating = False
Application.EnableEvents = False 'désactive les évènements
If FilterMode Then ShowAllData 'si la feuille est filtré
[C:F].ClearContents 'RAZ
Me.[C5].Resize((NbL + 1) \ 2).FormulaR1C1 = "=INDEX(" & AdrA & ",(ROW()-5)*2+1)"
Me.[F5].Resize(NbL \ 2).FormulaR1C1 = "=INDEX(" & AdrA & ",(ROW()-4)*2)"
Application.EnableEvents = True 'réactive les évènements
End Sub