How to display more data in the tooltip of UWP Charts

  <Page.DataContext>
        <local:ViewModel/>
    </Page.DataContext>
    <Page.Resources>
        <DataTemplate x:Key="tooltipTemplate">
            <StackPanel Orientation="Horizontal">
                <!--Template element has DataContext as its Segment named Item. From it, you can access the correponding Model-->
                <TextBlock  FontFamily="Segoe UI"  Foreground="White">
                      <Run Text="{Binding Item.Country}"/>
                      <Run Text=":"/>  
                      <Run Text="{Binding Item.Population}"/>
                </TextBlock>
            </StackPanel>
        </DataTemplate>
    </Page.Resources>
    <StackPanel Margin="40">
        <syncfusion:SfChart Header="Population growth" Width="353" Height="298">
            <syncfusion:SfChart.PrimaryAxis>
                <syncfusion:CategoryAxis/>
            </syncfusion:SfChart.PrimaryAxis>
            <syncfusion:SfChart.SecondaryAxis>
                <syncfusion:NumericalAxis/>
            </syncfusion:SfChart.SecondaryAxis>
            <syncfusion:ColumnSeries 
                         ItemsSource="{Binding Data}"
                         XBindingPath="Country"
                         YBindingPath="Population"
                         ShowTooltip="True"
                         TooltipTemplate="{StaticResource tooltipTemplate}"/>
        </syncfusion:SfChart>
    </StackPanel>