Sub ajoutligne()
NbLignes = Range("A1").End(xlDown).Row
multiple = 21
NbAjout = 6
fin = Int(NbLignes / 21)
i = 0
Do
Rows((multiple + 1) + (multiple + 6) * i).EntireRow.Insert
Rows((multiple + 1) + (multiple + 6) * i).EntireRow.Insert
Rows((multiple + 1) + (multiple + 6) * i).EntireRow.Insert
Rows((multiple + 1) + (multiple + 6) * i).EntireRow.Insert
Rows((multiple + 1) + (multiple + 6) * i).EntireRow.Insert
Rows((multiple + 1) + (multiple + 6) * i).EntireRow.Insert
NbLignes = NbLignes + 6
i = i + 1
Loop Until i = fin
End Sub