Sub Macro2()
Dim n As Integer, Plage As Range
Application.ScreenUpdating = False
For n = 1 To Range("F5000").End(xlUp).Row
If Range("F" & n) <> "tarif" Then
If Plage Is Nothing Then
Set Plage = Rows(n)
Else
Set Plage = Union(Rows(n), Plage)
End If
End If
Next n
Plage.Delete
Application.ScreenUpdating = True
End Sub