app/views/data_interactive/_group.html.erb
<div class="row top-buffer">
<form class="form-horizontal">
<div class="form-group">
<label class="col-md-2 control-label" for="group">Group by</label>
<div class="col-md-4">
<select class="form-control" id="group" data-bind="options: availableGroups, optionsCaption: '', value: group"></select><br>
</div>
</div>
</form>
</div>