Sub test()
Dim v_Lig As Long, v_DL As Long
v_DL = Range("A" & Rows.Count).End(xlUp).Row
For v_Lig = 6 To v_DL Step 6
Cells(v_Lig, "A").Insert Shift:=xlDown, CopyOrigin:=xlFormatFromLeftOrAbove
Next v_Lig
End Sub
Sub testV2()
Dim v_Lig As Long, v_DL As Long
v_DL = Range("A" & Rows.Count).End(xlUp).Row
For v_Lig = 6 To v_DL Step 6
Rows(v_Lig).Insert Shift:=xlDown
Next v_Lig
End Sub