diff --git a/f8/app.cc b/f8/app.cc
index 549cd54..2cda953 100644
--- a/f8/app.cc
+++ b/f8/app.cc
@@ -79,6 +79,7 @@ namespace f8
         user_app_ = user_app;
         int delta_time = 0;
         if (Init()) {
+            a8::tick_t last_stat_tick = a8::XGetTickCount();
             while (!Terminated()) {
                 a8::tick_t begin_tick = a8::XGetTickCount();
                 nowtime_ = time(nullptr);
@@ -92,7 +93,12 @@ namespace f8
                 }
                 Schedule();
                 end_tick = a8::XGetTickCount();
-                delta_time = end_tick - begin_tick;
+                if (end_tick - last_stat_tick > 0) {
+                    delta_time = end_tick - last_stat_tick;
+                    last_stat_tick = end_tick;
+                } else {
+                    delta_time = 0;
+                }
             }
             UnInit();
         }