diff --git a/calcrule_contribution_income_percentage/calculation_rule.py b/calcrule_contribution_income_percentage/calculation_rule.py
index 21dca7d..1fe0c08 100644
--- a/calcrule_contribution_income_percentage/calculation_rule.py
+++ b/calcrule_contribution_income_percentage/calculation_rule.py
@@ -23,12 +23,12 @@ class ContributionValuationRuleNoDependant(AbsCalculationRule):
     type = "account_receivable"
     sub_type = "contribution"
 
-    signal_get_rule_name = Signal(providing_args=[])
-    signal_get_rule_details = Signal(providing_args=[])
-    signal_get_param = Signal(providing_args=[])
-    signal_get_linked_class = Signal(providing_args=[])
-    signal_calculate_event = Signal(providing_args=[])
-    signal_convert_from_to = Signal(providing_args=[])
+    signal_get_rule_name = Signal([])
+    signal_get_rule_details = Signal([])
+    signal_get_param = Signal([])
+    signal_get_linked_class = Signal([])
+    signal_calculate_event = Signal([])
+    signal_convert_from_to = Signal([])
 
     @classmethod
     def ready(cls):