diff --git a/account_financial_report_qweb/__openerp__.py b/account_financial_report_qweb/__openerp__.py
index 4443bdc8..97ba3ed2 100644
--- a/account_financial_report_qweb/__openerp__.py
+++ b/account_financial_report_qweb/__openerp__.py
@@ -5,7 +5,7 @@
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
 {
     'name': 'QWeb Financial Reports',
-    'version': '9.0.1.0.3',
+    'version': '9.0.1.0.4',
     'category': 'Reporting',
     'summary': 'OCA Financial Reports',
     'author': 'Camptocamp SA,'
diff --git a/account_financial_report_qweb/report/__init__.py b/account_financial_report_qweb/report/__init__.py
index fb0e633c..d3746c0d 100644
--- a/account_financial_report_qweb/report/__init__.py
+++ b/account_financial_report_qweb/report/__init__.py
@@ -7,6 +7,7 @@
 import logging
 _logger = logging.getLogger(__name__)
 
+from . import abstract_report
 from . import aged_partner_balance
 from . import general_ledger
 from . import open_items
diff --git a/account_financial_report_qweb/report/abstract_report.py b/account_financial_report_qweb/report/abstract_report.py
new file mode 100644
index 00000000..3b4d8778
--- /dev/null
+++ b/account_financial_report_qweb/report/abstract_report.py
@@ -0,0 +1,22 @@
+# -*- coding: utf-8 -*-
+# Copyright 2018 Camptocamp SA
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+
+from openerp import models
+
+
+class AbstractReport(models.AbstractModel):
+    _name = 'report_qweb_abstract'
+
+    def _transient_clean_rows_older_than(self, cr, seconds):
+        assert self._transient, \
+            "Model %s is not transient, it cannot be vacuumed!" % self._name
+        # Never delete rows used in last 5 minutes
+        seconds = max(seconds, 300)
+        query = """
+DELETE FROM """ + self._table + """
+WHERE
+    COALESCE(write_date, create_date, (now() at time zone 'UTC'))::timestamp
+    < ((now() at time zone 'UTC') - interval %s)
+"""
+        cr.execute(query, ("%s seconds" % seconds,))
diff --git a/account_financial_report_qweb/report/aged_partner_balance.py b/account_financial_report_qweb/report/aged_partner_balance.py
index 131cccee..ef8501c9 100644
--- a/account_financial_report_qweb/report/aged_partner_balance.py
+++ b/account_financial_report_qweb/report/aged_partner_balance.py
@@ -19,6 +19,7 @@ class AgedPartnerBalanceReport(models.TransientModel):
     """
 
     _name = 'report_aged_partner_balance_qweb'
+    _inherit = 'report_qweb_abstract'
 
     # Filters fields, used for data computation
     date_at = fields.Date()
@@ -41,6 +42,7 @@ class AgedPartnerBalanceReport(models.TransientModel):
 class AgedPartnerBalanceReportAccount(models.TransientModel):
 
     _name = 'report_aged_partner_balance_qweb_account'
+    _inherit = 'report_qweb_abstract'
     _order = 'code ASC'
 
     report_id = fields.Many2one(
@@ -84,6 +86,7 @@ class AgedPartnerBalanceReportAccount(models.TransientModel):
 class AgedPartnerBalanceReportPartner(models.TransientModel):
 
     _name = 'report_aged_partner_balance_qweb_partner'
+    _inherit = 'report_qweb_abstract'
 
     report_account_id = fields.Many2one(
         comodel_name='report_aged_partner_balance_qweb_account',
@@ -128,6 +131,7 @@ ORDER BY
 class AgedPartnerBalanceReportLine(models.TransientModel):
 
     _name = 'report_aged_partner_balance_qweb_line'
+    _inherit = 'report_qweb_abstract'
 
     report_partner_id = fields.Many2one(
         comodel_name='report_aged_partner_balance_qweb_partner',
@@ -149,6 +153,7 @@ class AgedPartnerBalanceReportLine(models.TransientModel):
 class AgedPartnerBalanceReportMoveLine(models.TransientModel):
 
     _name = 'report_aged_partner_balance_qweb_move_line'
+    _inherit = 'report_qweb_abstract'
 
     report_partner_id = fields.Many2one(
         comodel_name='report_aged_partner_balance_qweb_partner',
diff --git a/account_financial_report_qweb/report/general_ledger.py b/account_financial_report_qweb/report/general_ledger.py
index 6c05e450..872f5615 100644
--- a/account_financial_report_qweb/report/general_ledger.py
+++ b/account_financial_report_qweb/report/general_ledger.py
@@ -22,6 +22,7 @@ class GeneralLedgerReport(models.TransientModel):
     """
 
     _name = 'report_general_ledger_qweb'
+    _inherit = 'report_qweb_abstract'
 
     # Filters fields, used for data computation
     date_from = fields.Date()
@@ -71,6 +72,7 @@ class GeneralLedgerReport(models.TransientModel):
 class GeneralLedgerReportAccount(models.TransientModel):
 
     _name = 'report_general_ledger_qweb_account'
+    _inherit = 'report_qweb_abstract'
     _order = 'code ASC'
 
     report_id = fields.Many2one(
@@ -112,6 +114,7 @@ class GeneralLedgerReportAccount(models.TransientModel):
 class GeneralLedgerReportPartner(models.TransientModel):
 
     _name = 'report_general_ledger_qweb_partner'
+    _inherit = 'report_qweb_abstract'
 
     report_account_id = fields.Many2one(
         comodel_name='report_general_ledger_qweb_account',
@@ -157,6 +160,7 @@ ORDER BY
 class GeneralLedgerReportMoveLine(models.TransientModel):
 
     _name = 'report_general_ledger_qweb_move_line'
+    _inherit = 'report_qweb_abstract'
 
     report_account_id = fields.Many2one(
         comodel_name='report_general_ledger_qweb_account',
diff --git a/account_financial_report_qweb/report/open_items.py b/account_financial_report_qweb/report/open_items.py
index 96350269..640798cd 100644
--- a/account_financial_report_qweb/report/open_items.py
+++ b/account_financial_report_qweb/report/open_items.py
@@ -17,6 +17,7 @@ class OpenItemsReport(models.TransientModel):
     """
 
     _name = 'report_open_items_qweb'
+    _inherit = 'report_qweb_abstract'
 
     # Filters fields, used for data computation
     date_at = fields.Date()
@@ -39,6 +40,7 @@ class OpenItemsReport(models.TransientModel):
 class OpenItemsReportAccount(models.TransientModel):
 
     _name = 'report_open_items_qweb_account'
+    _inherit = 'report_qweb_abstract'
     _order = 'code ASC'
 
     report_id = fields.Many2one(
@@ -68,6 +70,7 @@ class OpenItemsReportAccount(models.TransientModel):
 class OpenItemsReportPartner(models.TransientModel):
 
     _name = 'report_open_items_qweb_partner'
+    _inherit = 'report_qweb_abstract'
 
     report_account_id = fields.Many2one(
         comodel_name='report_open_items_qweb_account',
@@ -108,6 +111,7 @@ ORDER BY
 class OpenItemsReportMoveLine(models.TransientModel):
 
     _name = 'report_open_items_qweb_move_line'
+    _inherit = 'report_qweb_abstract'
 
     report_partner_id = fields.Many2one(
         comodel_name='report_open_items_qweb_partner',
diff --git a/account_financial_report_qweb/report/trial_balance.py b/account_financial_report_qweb/report/trial_balance.py
index 80b30f9a..f7b09641 100644
--- a/account_financial_report_qweb/report/trial_balance.py
+++ b/account_financial_report_qweb/report/trial_balance.py
@@ -17,6 +17,7 @@ class TrialBalanceReport(models.TransientModel):
     """
 
     _name = 'report_trial_balance_qweb'
+    _inherit = 'report_qweb_abstract'
 
     # Filters fields, used for data computation
     date_from = fields.Date()
@@ -45,6 +46,7 @@ class TrialBalanceReport(models.TransientModel):
 class TrialBalanceReportAccount(models.TransientModel):
 
     _name = 'report_trial_balance_qweb_account'
+    _inherit = 'report_qweb_abstract'
     _order = 'code ASC'
 
     report_id = fields.Many2one(
@@ -78,6 +80,7 @@ class TrialBalanceReportAccount(models.TransientModel):
 class TrialBalanceReportPartner(models.TransientModel):
 
     _name = 'report_trial_balance_qweb_partner'
+    _inherit = 'report_qweb_abstract'
 
     report_account_id = fields.Many2one(
         comodel_name='report_trial_balance_qweb_account',