diff --git a/plexpy/libraries.py b/plexpy/libraries.py
index 9f5136d9..91c27a33 100644
--- a/plexpy/libraries.py
+++ b/plexpy/libraries.py
@@ -819,8 +819,8 @@ class Libraries(object):
         if grouping is None:
             grouping = plexpy.CONFIG.GROUP_HISTORY_TABLES
 
-        if query_days is not None:
-            query_days = map(int, query_days.split(","))
+        if query_days and query_days is not None:
+            query_days = map(helpers.cast_to_int, query_days.split(','))
         else:
             query_days = [1, 7, 30, 0]
 
diff --git a/plexpy/users.py b/plexpy/users.py
index 0a5f7621..e4b36cd5 100644
--- a/plexpy/users.py
+++ b/plexpy/users.py
@@ -441,8 +441,8 @@ class Users(object):
         if grouping is None:
             grouping = plexpy.CONFIG.GROUP_HISTORY_TABLES
 
-        if query_days is not None:
-            query_days = map(int, query_days.split(","))
+        if query_days and query_days is not None:
+            query_days = map(helpers.cast_to_int, query_days.split(','))
         else:
             query_days = [1, 7, 30, 0]