diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/timetracker/TimeTracker.java b/ganttzk/src/main/java/org/zkoss/ganttz/timetracker/TimeTracker.java
index 1547d5c48..10806dd79 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/timetracker/TimeTracker.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/timetracker/TimeTracker.java
@@ -246,15 +246,6 @@ public class TimeTracker {
         }
     }
 
-    private Date endPlusOneYear(Task task) {
-        return new LocalDate(task.getEndDate()).plusYears(1).toDateMidnight().toDate();
-    }
-
-    private Date startMinusOneYear(Task task) {
-        return new LocalDate(task.getBeginDate()).minusYears(1)
-                .toDateMidnight().toDate();
-    }
-
     private Date endPlusOneMonth(Task task) {
         return new LocalDate(task.getEndDate()).plusMonths(1).toDateMidnight().toDate();
     }