diff --git a/src/client/stores/CalculationStore/Effects/computed.js b/src/client/stores/CalculationStore/Effects/computed.js
index f241bc4..7b485f1 100644
--- a/src/client/stores/CalculationStore/Effects/computed.js
+++ b/src/client/stores/CalculationStore/Effects/computed.js
@@ -55,8 +55,9 @@ const computedEffects = {
       }
     }
   },
-  insKaskoPriceLeasePeriod: () =>
-    customValues.insKaskoPriceLeasePeriod.call(this).toFixed(2),
+  insKaskoPriceLeasePeriod() {
+    return customValues.insKaskoPriceLeasePeriod.call(this).toFixed(2);
+  },
 };
 
 export default computedEffects;