Sub Bouton1_Clic()
Application.ScreenUpdating = False
Dim t(1 To 10)
For i = 2 To Range("F65535").End(xlUp).Row
t(Cells(i, 6)) = t(Cells(i, 6)) + 1
Cells(i, 2) = t(Cells(i, 6))
If Cells(i + 1, 6) <> Cells(i, 6) Then t(Cells(i, 6)) = 0
Next i
Application.ScreenUpdating = True
End Sub