Macro to Insert Line

Hi,
Please need help on macro,
I want to insert a line after every change in order number.
macro should insert the blank line and should copy the same order number and in column STOCK_CODE it should type "DELIVERY"

Thanks in advance four your kind help.

Sub InsertLine()
    Dim i As Long
    For i = Cells(Rows.Count, 1).End(xlUp).Row To 2 Step -1
        If Cells(i - 1, 1) <> Cells(i, 1) Then
            Rows(i).Insert
        End If
    Next
End Sub

ORDER_DATE ACCOUNT_REF ORDER_TYPE ORDER_REF STOCK_CODE qty_order
02/02/2013 ZENMART SO 101556 R922003-AZ 1
02/02/2013 ZENMART SO 101557 I200054-AZ 2
02/02/2013 ZENMART SO 101557 E300012-AZ 1
02/02/2013 ZENMART SO 101558 C111317-AZ 1
02/02/2013 ZENMART SO 101558 J130138-AZ 1 BEFORE
02/02/2013 ZENMART SO 101558 C110113-AZ 1
02/02/2013 ZENMART SO 101559 P800113-AZ 1
02/02/2013 ZENMART SO 101560 R922000-AZ 1
03/02/2013 ZENMART SO 101561 C111330-AZ 2

ORDER_DATE ACCOUNT_REF ORDER_TYPE ORDER_REF STOCK_CODE qty_order
02/02/2013 ZENMART SO 101556 R922003-AZ 1
02/02/2013 ZENMART SO 101556 DELIVERY 1
02/02/2013 ZENMART SO 101557 I200054-AZ 2
02/02/2013 ZENMART SO 101557 E300012-AZ 1
02/02/2013 ZENMART SO 101557 DELIVERY 1
02/02/2013 ZENMART SO 101558 C111317-AZ 1
02/02/2013 ZENMART SO 101558 J130138-AZ 1
02/02/2013 ZENMART SO 101558 C110113-AZ 1 AFTER
02/02/2013 ZENMART SO 101558 DELIVERY 1
02/02/2013 ZENMART SO 101559 P800113-AZ 1
02/02/2013 ZENMART SO 101559 DELIVERY 1
02/02/2013 ZENMART SO 101560 R922000-AZ 1
02/02/2013 ZENMART SO 101560 DELIVERY 1
03/02/2013 ZENMART SO 101561 C111330-AZ 2
03/02/2013 ZENMART SO 101561 DELIVERY 1