diff --git a/addons/hr_timesheet_sheet/hr_timesheet_sheet.py b/addons/hr_timesheet_sheet/hr_timesheet_sheet.py
index ceb661f2bb6..d89552f087e 100644
--- a/addons/hr_timesheet_sheet/hr_timesheet_sheet.py
+++ b/addons/hr_timesheet_sheet/hr_timesheet_sheet.py
@@ -41,18 +41,24 @@ class hr_timesheet_sheet(osv.osv):
         """ Compute the attendances, analytic lines timesheets and differences between them
             for all the days of a timesheet and the current day
         """
+        res = dict.fromkeys(ids, {
+            'total_attendance': 0.0,
+            'total_timesheet': 0.0,
+            'total_difference': 0.0,
+        })
+
+        cr.execute("""
+            SELECT sheet_id as id,
+                   sum(total_attendance) as total_attendance,
+                   sum(total_timesheet) as total_timesheet,
+                   sum(total_difference) as  total_difference
+            FROM hr_timesheet_sheet_sheet_day
+            WHERE sheet_id IN %s
+            GROUP BY sheet_id
+        """, (tuple(ids),))
+
+        res.update(dict((x.pop('id'), x) for x in cr.dictfetchall()))
 
-        res = {}
-        for sheet in self.browse(cr, uid, ids, context=context or {}):
-            res.setdefault(sheet.id, {
-                'total_attendance': 0.0,
-                'total_timesheet': 0.0,
-                'total_difference': 0.0,
-            })
-            for period in sheet.period_ids:
-                res[sheet.id]['total_attendance'] += period.total_attendance
-                res[sheet.id]['total_timesheet'] += period.total_timesheet
-                res[sheet.id]['total_difference'] += period.total_attendance - period.total_timesheet
         return res
 
     def check_employee_attendance_state(self, cr, uid, sheet_id, context=None):