diff --git a/Editor/EventManagerEditor.cs b/Editor/EventManagerEditor.cs
index ba2c24e..b907d3e 100644
--- a/Editor/EventManagerEditor.cs
+++ b/Editor/EventManagerEditor.cs
@@ -8,13 +8,13 @@ namespace Utils
     {
         public override void OnInspectorGUI()
         {
-            EventManager myTarget = (EventManager)target;
+            EventManager eventManager = (EventManager)target;
             GUILayout.BeginHorizontal();
             GUILayout.Label("Update");
             if (Application.isPlaying)
             {
                 GUILayout.FlexibleSpace();
-                GUILayout.Label(myTarget.UpdateLength().ToString());
+                GUILayout.Label(eventManager.UpdateLength.ToString());
             }
             GUILayout.EndHorizontal();
             GUILayout.BeginHorizontal();
@@ -22,7 +22,7 @@ namespace Utils
             if (Application.isPlaying)
             {
                 GUILayout.FlexibleSpace();
-                GUILayout.Label(myTarget.FixedUpdateLength().ToString());
+                GUILayout.Label(eventManager.FixedUpdateLength.ToString());
             }
             GUILayout.EndHorizontal();
             GUILayout.BeginHorizontal();
@@ -30,7 +30,7 @@ namespace Utils
             if (Application.isPlaying)
             {
                 GUILayout.FlexibleSpace();
-                GUILayout.Label(myTarget.LateUpdateLength().ToString());
+                GUILayout.Label(eventManager.LateUpdateLength.ToString());
             }
             GUILayout.EndHorizontal();
         }
diff --git a/Runtime/EventManager.cs b/Runtime/EventManager.cs
index 315f8d0..78719e6 100644
--- a/Runtime/EventManager.cs
+++ b/Runtime/EventManager.cs
@@ -28,19 +28,52 @@ namespace Utils
             OnLateUpdated?.Invoke();
         }
 
-        public int UpdateLength()
+        public int UpdateLength
         {
-            return (int)OnUpdated?.GetInvocationList().Length;
+            get
+            {
+                var list = OnUpdated?.GetInvocationList();
+                if (list != null)
+                {
+                    return list.Length;
+                }
+                else
+                {
+                    return 0;
+                }
+            }
         }
 
-        public int FixedUpdateLength()
+        public int FixedUpdateLength
         {
-            return (int)OnFixedUpdated?.GetInvocationList().Length;
+            get
+            {
+                var list = OnFixedUpdated?.GetInvocationList();
+                if (list != null)
+                {
+                    return list.Length;
+                }
+                else
+                {
+                    return 0;
+                }
+            }
         }
 
-        public int LateUpdateLength()
+        public int LateUpdateLength
         {
-            return (int)OnLateUpdated?.GetInvocationList().Length;
+            get
+            {
+                var list = OnLateUpdated?.GetInvocationList();
+                if (list != null)
+                {
+                    return list.Length;
+                }
+                else
+                {
+                    return 0;
+                }
+            }
         }
     }
 }