diff --git a/mis_builder/models/mis_builder.py b/mis_builder/models/mis_builder.py
index 8118f380..42684029 100644
--- a/mis_builder/models/mis_builder.py
+++ b/mis_builder/models/mis_builder.py
@@ -320,7 +320,7 @@ class MisReportKpi(models.Model):
     def render(self, lang_id, value):
         """ render a KPI value as a unicode string, ready for display """
         assert len(self) == 1
-        if value is None or value == AccountingNone:
+        if value is None or value is AccountingNone:
             return ''
         elif self.type == 'num':
             return self._render_num(lang_id, value, self.divider,
diff --git a/mis_builder/tests/mis.report.instance.period.csv b/mis_builder/tests/mis.report.instance.period.csv
index 72250953..73bd7580 100644
--- a/mis_builder/tests/mis.report.instance.period.csv
+++ b/mis_builder/tests/mis.report.instance.period.csv
@@ -1,2 +1,2 @@
-"id","duration","name","offset","type","sequence"
-"mis_report_instance_period_test","1","today","","Day",""
\ No newline at end of file
+"id","duration","name","offset","type","sequence","mode"
+"mis_report_instance_period_test","1","today","","Day","","relative"
diff --git a/mis_builder/tests/test_mis_builder.py b/mis_builder/tests/test_mis_builder.py
index 637aed32..4e84f7aa 100644
--- a/mis_builder/tests/test_mis_builder.py
+++ b/mis_builder/tests/test_mis_builder.py
@@ -39,15 +39,17 @@ class TestMisBuilder(common.TransactionCase):
         self.assertDictContainsSubset(
             {'content':
                 [{'kpi_name': u'total test',
-                  'default_style': False,
+                  'default_style': '',
+                  'default_xlsx_style': {},
                   'cols': [{'period_id': self.ref('mis_builder.'
                                                   'mis_report_instance_'
                                                   'period_test'),
-                            'style': None,
+                            'style': '',
+                            'xlsx_style': {},
                             'prefix': False,
                             'suffix': False,
-                            'expr': 'len(test)',
-                            'val_c': 'total_test = len(test)',
+                            'expr': u'len(test)',
+                            'val_c': u'total_test = len(test)',
                             'val': 0,
                             'val_r': u'\u202f0\xa0',
                             'is_percentage': False,
@@ -57,6 +59,14 @@ class TestMisBuilder(common.TransactionCase):
              'header':
                  [{'kpi_name': '',
                    'cols': [{'date': '07/31/2014',
-                             'name': u'today'}]
-                   }],
+                             'colspan': 1,
+                             'name': u'today',
+                             }],
+                   },
+                   {'kpi_name': '',
+                    'cols': [{'colspan': 1,
+                              'name': '',
+                              }],
+                   },
+                  ],
              }, data)