diff --git a/core/views/user.py b/core/views/user.py
index 286a3a92..027a7edc 100644
--- a/core/views/user.py
+++ b/core/views/user.py
@@ -21,9 +21,11 @@
 # Place - Suite 330, Boston, MA 02111-1307, USA.
 #
 #
+import itertools
 
 # This file contains all the views that concern the user model
 from datetime import date, timedelta
+from operator import itemgetter
 from smtplib import SMTPException
 
 from django.conf import settings
@@ -665,9 +667,15 @@ class UserAccountView(UserAccountBase):
         kwargs["refilling_month"] = self.expense_by_month(
             Refilling.objects.filter(customer=self.object.customer)
         )
-        kwargs["invoices_month"] = self.expense_by_month(
-            Invoice.objects.filter(user=self.object)
-        )
+        kwargs["invoices_month"] = [
+            # the django ORM removes the `group by` clause in this query,
+            # so a little of post-processing is needed
+            {"grouped_date": key, "total": sum(i["total"] for i in group)}
+            for key, group in itertools.groupby(
+                self.expense_by_month(Invoice.objects.filter(user=self.object)),
+                key=itemgetter("grouped_date"),
+            )
+        ]
         kwargs["etickets"] = self.object.customer.buyings.exclude(product__eticket=None)
         return kwargs