Fix issue #454. Thanks to Andrei Korostelev @kindkaktus for the issue and the solution.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

HISTORY.rst

@@ -108,7 +108,8 @@
 - Add support for groups ACLs.
 - Sort permission namespaces and permissions in the role permission views.
 - Invert the columns in the ACL detail view.
-
+- Fix issue #454. Thanks to Andrei Korostelev @kindkaktus for the issue and the
+  solution.
 
 2.7.3 (2017-09-11)
 ==================

docs/releases/3.0.rst

@@ -423,5 +423,6 @@ Bugs fixed or issues closed
 ===========================
 
 * `GitLab issue #262 <https://gitlab.com/mayan-edms/mayan-edms/issues/262>`_ Event notifications
+* `GitLab issue #454 <https://gitlab.com/mayan-edms/mayan-edms/issues/454>`_ Invalid next month calculation in statistics app, causes failstop
 
 .. _PyPI: https://pypi.python.org/pypi/mayan-edms/

mayan/apps/documents/statistics.py

@@ -98,7 +98,7 @@ def total_document_per_month():
     for month in range(1, datetime.date.today().month + 1):
         next_month = month + 1
 
-        if next_month == 12:
+        if month == 12:
             next_month = 1
             year = this_year + 1
         else:
@@ -129,7 +129,7 @@ def total_document_version_per_month():
     for month in range(1, datetime.date.today().month + 1):
         next_month = month + 1
 
-        if next_month == 12:
+        if month == 12:
             next_month = 1
             year = this_year + 1
         else:
@@ -160,7 +160,7 @@ def total_document_page_per_month():
     for month in range(1, datetime.date.today().month + 1):
         next_month = month + 1
 
-        if next_month == 12:
+        if month == 12:
             next_month = 1
             year = this_year + 1
         else: