listview / dataview problemer

Hej.

Her er min kode:

Private Sub FillList()

        lstBetAftTotal.Clear()
        lstBetAftTotal.View = View.Details

        Dim ds As DataSet = Util.FillDataSet("select land,substr(dato,0,2) as dag,dato,antal,navn from betalingsaftaler where substr(dato,4,2) = '12' and substr(dato,7,10) = '2004' and land = 'DK'", "test")



        Dim dv As DataView

        dv = New DataView(ds.Tables("test"))


        Dim cnSQL As OracleConnection
        Dim cmSQL As OracleCommand
        Dim drSQL As OracleDataReader
        Dim strSQL As String
        Dim strID As String

        strSQL = "select distinct(navn) as navn,sum(antal) as antal from betalingsaftaler where substr(dato,4,2) = '12' and substr(dato,7,10) = '2004' and land = 'DK' group by navn"
        cnSQL = New OracleConnection(Util.DBConn())
        cnSQL.Open()
        cmSQL = New OracleCommand(strSQL, cnSQL)
        drSQL = cmSQL.ExecuteReader()


        Dim myimage As New ImageList
        myimage.Images.Add(Bitmap.FromFile("user2.bmp"))
        myimage.Images.Add(Bitmap.FromFile("twouser.bmp"))
        lstBetAftTotal.SmallImageList = myimage


   

        Dim myfont As Font = Me.Font

        Dim tal As Integer = 0

        'This sets the columns of the ListView to the same column names of the table in the database
        With lstBetAftTotal
            .Columns.Add(("Navn"), 55, HorizontalAlignment.Left)




            For tal = 1 To Date.DaysInMonth(2004, 12)



                .Columns.Add(tal, 30, HorizontalAlignment.Right)

            Next
        End With



        'Now scrolling through the DataReader and populating the ListView with the data
        While drSQL.Read()

            Dim ls As New ListViewItem(drSQL.Item("navn").ToString())
            ls.UseItemStyleForSubItems = False


            dv.RowFilter = "navn = '" & drSQL.Item("navn").ToString() & "'"
            'dv.Sort = "dag DESC"



            For tal = 0 To Date.DaysInMonth(2004, 12)

                ls.SubItems.Add(dv.Item(tal).Item("antal").ToString())


          Next

            ls.ImageIndex = 0

            lstBetAftTotal.Items.Add(ls)

        End While

        lstBetAftTotal.Refresh()

        DataGrid1.DataSource = dv


    End Sub


Mit problem er mine subitems i listviewet. Jeg laver en løkke der tæller antal dage in en måned igennem. Jeg tjekker så på mit dataviews index for at udskrive en værdi til et subitem. Men Hvordan indsætter jeg et blankt subitem når index'et ikke findes i dataviewet????