Rectified a logic mistake

ecar.py

@@ -64,8 +64,9 @@ class c_ecar_comparator:
         y = 0
         m = 1
         months_a_year = 12.0
-        costs_a_month = self.calculate_costs(y, m)
-        savings_a_month = costs_a_month[1]-costs_a_month[0]
+        # Insurance and taxes need to be payed anyway
+        relevant_costs_a_year = self.settings_extractor.get_driving() + self.settings_extractor.get_maintenance()
+        savings_a_month = (relevant_costs_a_year[1]-relevant_costs_a_year[0]) / months_a_year
         months_till_amortized = self.settings_extractor.get_purchase()[0] / savings_a_month
         kilometers = months_till_amortized * self.settings_extractor.get_kilometers() / months_a_year
         months_till_amortized = np.ceil(months_till_amortized)