I try to implement IRenderLabel Interface for Column Chart but it didnt work (LabelRenderer ist not call):

    public class LabelRenderer : IRenderLabel
    {
        /// <summary>
        /// </summary>
        /// <param name="context"></param>
        /// <returns></returns>
        public string ToString(Hashtable context)
        {
            string resultString = string.Empty;
            double dataValue = (double)context["DATA_VALUE"];
            int dataValueModulo = 0;

            if(dataValue >= 1000000000 )
            {
                dataValueModulo =(int)dataValue % 1000000000;
                resultString = dataValueModulo.ToString() + "Mrd.";
            }

            return resultString;
        }
    }

---------------------

            ToRenderColumnChart.Axis.Y.Labels.ItemFormatString = "<DATA_VALUE:n0>";
            Hashtable LabelHashTable = new Hashtable();
            LabelHashTable.Add("DATA_VALUE", new LabelRenderer());
            ToRenderColumnChart.LabelHash = LabelHashTable;

Please Help me, asp.

Thank you very much