diff --git a/admin_tools_stats/models.py b/admin_tools_stats/models.py
index 7e4ec84..e510925 100644
--- a/admin_tools_stats/models.py
+++ b/admin_tools_stats/models.py
@@ -1058,6 +1058,7 @@ def _get_dynamic_choices(
                 choices.update(
                     ((i, (i, fchoices[i] if i in fchoices else i)) for i in choices_queryset),
                 )
+                choices.update([("None", (None, None))])
                 if count_limit:
                     choices.update(
                         [("other", (other_choices_queryset, "other"))],