diff --git a/src/spaceone/dashboard/manager/data_table_manager/data_source_manager.py b/src/spaceone/dashboard/manager/data_table_manager/data_source_manager.py
index 0b46cf9..c058015 100644
--- a/src/spaceone/dashboard/manager/data_table_manager/data_source_manager.py
+++ b/src/spaceone/dashboard/manager/data_table_manager/data_source_manager.py
@@ -223,8 +223,8 @@ def _change_datetime_format(results: list) -> list:
 
     def _change_date_by_timediff(self, date: str) -> str:
         dt = self._get_datetime_from_str(date)
-        years = self.timediff.get("years", 0)
-        months = self.timediff.get("months", 0)
+        years = int(self.timediff.get("years", 0))
+        months = int(self.timediff.get("months", 0))
 
         if years:
             dt = dt - relativedelta(years=years)