diff --git a/product/ERP5/Document/MonthlyRangeMovementGroup.py b/product/ERP5/Document/MonthlyRangeMovementGroup.py
new file mode 100644
index 0000000000000000000000000000000000000000..1bc0e60c718c28c8a8d1f1931daf6a1af1d6b8b5
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+++ b/product/ERP5/Document/MonthlyRangeMovementGroup.py
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+##############################################################################
+#
+# Copyright (c) 2009 Nexedi SA and Contributors. All Rights Reserved.
+#
+# WARNING: This program as such is intended to be used by professional
+# programmers who take the whole responsibility of assessing all potential
+# consequences resulting from its eventual inadequacies and bugs
+# End users who are looking for a ready-to-use solution with commercial
+# guarantees and support are strongly adviced to contract a Free Software
+# Service Company
+#
+# This program is Free Software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
+# 02110-1301, USA.
+#
+##############################################################################
+
+from Products.ERP5.Document.MovementGroup import MovementGroup
+from Products.ERP5Type.DateUtils import atTheEndOfPeriod
+
+
+class MonthlyRangeMovementGroup(MovementGroup):
+  """
+  The purpose of MovementGroup is to define how movements are grouped,
+  and how values are updated from simulation movements.
+
+  This movement group is used to collect movements that have datetime
+  which is in the same month.
+  """
+  meta_type = 'ERP5 Movement Group'
+  portal_type = 'Monthly Range Movement Group'
+
+  def _getPropertyDict(self, movement, **kw):
+    """Gather start_date and stop_date, converge them to the end of month.
+    """
+    property_dict = {}
+    for property_name in ('start_date', 'stop_date'):
+      date = movement.getProperty(property_name, None)
+      if date is not None:
+        end_of_month = atTheEndOfPeriod(date, 'month')-1
+        property_dict[property_name] = end_of_month
+    return property_dict
+
+  def test(self, object, property_dict, property_list=None, **kw):
+    start_date = property_dict.get('start_date', None)
+    stop_date = property_dict.get('stop_date', None)
+    if start_date is None or stop_date is None:
+      return False, property_dict
+
+    target_start_date = object.getProperty('start_date', None)
+    target_stop_date = object.getProperty('stop_date', None)
+    if target_start_date is None or target_stop_date is None:
+      return False, property_dict
+
+    if (start_date.year()==target_start_date.year() and
+        start_date.month()==target_start_date.month() and
+        stop_date.year()==target_stop_date.year() and
+        stop_date.month()==target_stop_date.month()):
+      return True, property_dict
+    else:
+      return False, property_dict