diff --git a/sale.py b/sale.py
index 213c657..83868e6 100644
--- a/sale.py
+++ b/sale.py
@@ -80,8 +80,7 @@ class Sale(metaclass=PoolMeta):
             if (sale.state in cls._states_cached
                     and sale.untaxed_amount_cache is not None
                     and sale.tax_amount_cache is not None
-                    and sale.total_amount_cache is not None
-                    and sale.total_discount is not None):
+                    and sale.total_amount_cache is not None):
                 untaxed_amount[sale.id] = sale.untaxed_amount_cache
                 total_discount[sale.id] = sale.total_discount_cache
                 if compute_taxes: