diff --git a/analytics/tests/test_counts.py b/analytics/tests/test_counts.py
index 6d17a5b54c..2f7fbd86f9 100644
--- a/analytics/tests/test_counts.py
+++ b/analytics/tests/test_counts.py
@@ -67,15 +67,17 @@ class AnalyticsTestCase(TestCase):
         return Message.objects.create(**kwargs)
 
     # kwargs should only ever be a UserProfile or Stream.
-    def assertCountEquals(self, table, property, value, end_time = TIME_ZERO, interval = CountStat.HOUR,
-                          realm = None, **kwargs):
-        # type: (Type[BaseCount], Text, int, datetime, str, Optional[Realm], **models.Model) -> None
+    def assertCountEquals(self, table, property, value, subgroup=None, end_time=TIME_ZERO,
+                          interval=CountStat.HOUR, realm=None, **kwargs):
+        # type: (Type[BaseCount], Text, int, Optional[Text], datetime, str, Optional[Realm], **models.Model) -> None
         queryset = table.objects.filter(property=property, interval=interval, end_time=end_time) \
                                 .filter(**kwargs)
         if table is not InstallationCount:
             if realm is None:
                 realm = self.default_realm
             queryset = queryset.filter(realm=realm)
+        if subgroup is not None:
+            queryset = queryset.filter(subgroup=subgroup)
         self.assertEqual(queryset.values_list('value', flat=True)[0], value)
 
 # Tests manangement commands, backfilling, adding new stats, etc