<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid">
  <Grid.Resources>
    <xcdg:DataGridCollectionViewSource x:Key="cvs_orderdetails"
                                       Source="{Binding Source={x:Static Application.Current},
                                                        Path=OrderDetails}">
     <xcdg:DataGridCollectionViewSource.StatFunctions>
       <xcdg:CountFunction ResultPropertyName="orderid_count"
                           SourcePropertyName="OrderID"/>
       <xcdg:SumFunction ResultPropertyName="unitprice_sum"
                         SourcePropertyName="UnitPrice"/>
       <xcdg:SumFunction ResultPropertyName="quantity_sum" SourcePropertyName="Quantity"/>
     </xcdg:DataGridCollectionViewSource.StatFunctions>
     <xcdg:DataGridCollectionViewSource.GroupDescriptions>
       <xcdg:DataGridGroupDescription PropertyName="ProductID"/>      
 </xcdg:DataGridCollectionViewSource.GroupDescriptions>
    </xcdg:DataGridCollectionViewSource>
   <xcdg:StatResultConverter x:Key="valueConverter"/>
  </Grid.Resources>
  <DockPanel>
    <StackPanel Orientation="Horizontal" DockPanel.Dock="Top">
      <TextBlock Text="Total Orders: "/>
      <TextBlock Text="{Binding ElementName=OrderDetailsGrid,
                 Path=StatContext.orderid_count}"/>
    </StackPanel>
     <StackPanel Orientation="Horizontal" DockPanel.Dock="Top">
       <TextBlock Text="Average Unit Price: "/>
     <TextBlock Text="{Binding ElementName=OrderDetailsGrid,
                        Path=StatContext.unitprice_average,
                        Converter={StaticResource valueConverter},
                        ConverterParameter=f2}"/>
    </StackPanel>
    <xcdg:DataGridControl x:Name="OrderDetailsGrid"
                          ItemsSource="{Binding Source={StaticResource cvs_orderdetails}}"
                          DockPanel.Dock="Bottom">
      <xcdg:DataGridControl.DefaultGroupConfiguration>
        <xcdg:GroupConfiguration> 
        <xcdg:GroupConfiguration.Footers>
           <DataTemplate>
               <xcdg:StatRow>
               <xcdg:StatCell FieldName="UnitPrice"
                              ResultPropertyName="unitprice_sum"/>
               <xcdg:StatCell FieldName="Quantity"
                              ResultPropertyName="quantity_sum"/>
               <xcdg:StatCell FieldName="OrderID"
                              ResultPropertyName="orderid_count"/>
             </xcdg:StatRow>
           </DataTemplate>
         </xcdg:GroupConfiguration.Footers>
        </xcdg:GroupConfiguration>
      </xcdg:DataGridControl.DefaultGroupConfiguration>    
    </xcdg:DataGridControl>
  </DockPanel>
</Grid>