MainWindow.xaml

<dx:DXWindow
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:GroupFootersWPF"
    xmlns:dx="http://schemas.devexpress.com/winfx/2008/xaml/core"
        xmlns:dxg="http://schemas.devexpress.com/winfx/2008/xaml/grid" x:Class="GroupFootersWPF.MainWindow"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <dxg:GridControl x:Name="grid" ItemsSource="{Binding}">
            <dxg:GridControl.Columns>
                <dxg:GridColumn FieldName="Text"/>
                <dxg:GridColumn FieldName="Number0"/>
                <dxg:GridColumn FieldName="Number1"/>
                <dxg:GridColumn FieldName="Number2" Fixed="Left"/>
                <dxg:GridColumn FieldName="Group" GroupIndex="0"/>
            </dxg:GridControl.Columns>
            <dxg:GridControl.View>
                <dxg:TableView UseAnimationWhenExpanding="False" AllowFixedColumnMenu="True" GroupSummaryDisplayMode="AlignByColumns" ShowGroupFooters="True"/>
            </dxg:GridControl.View>
            <dxg:GridControl.GroupSummary>
                <dxg:GridSummaryItem FieldName="Text" SummaryType="Count" ShowInGroupColumnFooter="Text"/>
                <dxg:GridSummaryItem FieldName="Number0" SummaryType="Sum" ShowInGroupColumnFooter="Number0"/>
                <dxg:GridSummaryItem FieldName="Number1" SummaryType="Sum" ShowInGroupColumnFooter="Number1"/>
                <dxg:GridSummaryItem FieldName="Number2" SummaryType="Max" ShowInGroupColumnFooter="Number2"/>
            </dxg:GridControl.GroupSummary>
        </dxg:GridControl>
    </Grid>
</dx:DXWindow>