diff --git a/modules/sale/sale_reporting.py b/modules/sale/sale_reporting.py
index 8df510254f..a8c9f7b9da 100644
--- a/modules/sale/sale_reporting.py
+++ b/modules/sale/sale_reporting.py
@@ -24,7 +24,7 @@ from trytond.i18n import lazy_gettext
 
 def pairwise(iterable):
     a, b = tee(iterable)
-    next(b)
+    next(b, None)
     return zip_longest(a, b)
 
 
diff --git a/modules/stock/stock_reporting_margin.py b/modules/stock/stock_reporting_margin.py
index ce5aef73f4..557d9fd58f 100644
--- a/modules/stock/stock_reporting_margin.py
+++ b/modules/stock/stock_reporting_margin.py
@@ -24,7 +24,7 @@ from trytond.transaction import Transaction
 
 def pairwise(iterable):
     a, b = tee(iterable)
-    next(b)
+    next(b, None)
     return zip_longest(a, b)