diff --git a/AIParkingApplication/Statistic.cs b/AIParkingApplication/Statistic.cs
index feb5142..a9189f7 100644
--- a/AIParkingApplication/Statistic.cs
+++ b/AIParkingApplication/Statistic.cs
@@ -12,12 +12,12 @@ namespace AIParkingApplication
         private readonly Thread thrStatistics;
         private int timeCycle;
 
-        Label lblLoaiXe;
-        Label lblXeMay;
-        Label lblOto;
-        Label lblSoLuong;
-        Label lblSoLuongXeMay;
-        Label lblSoLuongOto;
+        private Label lblLoaiXe;
+        private Label lblXeMay;
+        private Label lblOto;
+        private Label lblSoLuong;
+        private Label lblSoLuongXeMay;
+        private Label lblSoLuongOto;
 
         public Statistic(string apiUrl, int timeCycle_Sec = 1)
         {