How to add text below the series in Silverlight OLAPChart?

public partial class MainPage : UserControl
    {
        private IOlapDataProvider dataProvider;
        public object OlapDataManager;
        public MainPage()
        {
            InitializeComponent();
            InitializeConnection();
            this.olapChart.Loaded += olapChart_Loaded; 
        }
        private void InitializeConnection()
        {
            Binding customBinding = new CustomBinding(new 
            BinaryMessageEncodingBindingElement(), new HttpTransportBindingElement { 
            MaxReceivedMessageSize = 2147483647 });
            EndpointAddress address = new EndpointAddress("http://bi.syncfusion.com/OlapWcfProject/Services/OlapManager.svc/binary");
            ChannelFactory<IOlapDataProvider> clientChannel = new    
            ChannelFactory<IOlapDataProvider>(customBinding, address);
            dataProvider = clientChannel.CreateChannel();
            OlapDataManager olapDataManager = new OlapDataManager();
            olapDataManager.DataProvider = dataProvider;
            olapDataManager.SetCurrentReport(CreateOlapReport());
            this.OlapDataManager = olapDataManager;
        }
void olapChart_Loaded(object sender, System.Windows.RoutedEventArgs e)
        {     
                      this.olapChart.OlapArea.PrimaryAxis.Header = "OLAP Chart";
        }
}

Partial Public Class MainPage
    Inherits UserControl
    Private dataProvider As IOlapDataProvider
    Public OlapDataManager As Object
    Public Sub New()
        InitializeComponent()
        InitializeConnection()
        AddHandler Me.olapChart.Loaded, AddressOf olapChart_Loaded   
    End Sub
Private Sub InitializeConnection()
         Binding customBinding = New CustomBinding(New    
         BinaryMessageEncodingBindingElement(), New HttpTransportBindingElement 
            {
        MaxReceivedMessageSize = 2147483647
            })
        Dim address As EndpointAddress = New EndpointAddress("http://bi.syncfusion.com/OlapWcfProject/Services/OlapManager.svc/binary")
        Dim clientChannel As ChannelFactory<IOlapDataProvider> =  New 
        ChannelFactory<IOlapDataProvider>(customBinding,address) 
        dataProvider = clientChannel.CreateChannel()
        Dim olapDataManager As OlapDataManager = New OlapDataManager()
        olapDataManager.DataProvider = dataProvider
        olapDataManager.SetCurrentReport(CreateOlapReport())
        Me.OlapDataManager = olapDataManager
End Sub
Private Sub olapChart_Loaded(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs)
        Me.olapChart.OlapArea.PrimaryAxis.Header = "OLAP Chart"
End Sub
End Class