diff --git a/library/include/mobilisis/calculate_price.h b/library/include/mobilisis/calculate_price.h
index 1e97e8e..0e5c62a 100644
--- a/library/include/mobilisis/calculate_price.h
+++ b/library/include/mobilisis/calculate_price.h
@@ -196,11 +196,25 @@ int CALCULATE_LIBRARY_API get_zone_nr(int zone = -1);
 int CALCULATE_LIBRARY_API compute_next_timestep(parking_tariff_t *tariff, int currentTimeMinutes, int UpDown);
 
 QList<int> CALCULATE_LIBRARY_API get_time_steps(Configuration *cfg);
-int CALCULATE_LIBRARY_API get_minimal_parkingtime(Configuration *cfg, PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING);
-int CALCULATE_LIBRARY_API get_maximal_parkingtime(Configuration *cfg, PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING);
-int CALCULATE_LIBRARY_API get_minimal_parkingprice(Configuration *cfg, PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING);
-int CALCULATE_LIBRARY_API get_maximal_parkingprice(Configuration *cfg, PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING);
-int CALCULATE_LIBRARY_API compute_product_price(Configuration const *cfg, PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING);
+
+int CALCULATE_LIBRARY_API get_minimal_parkingtime(Configuration *cfg,
+                                                  PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING,
+                                                  int paymentOptionIndex=0);
+
+int CALCULATE_LIBRARY_API get_maximal_parkingtime(Configuration *cfg,
+                                                  PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING,
+                                                  int paymentOptionIndex=0);
+
+int CALCULATE_LIBRARY_API get_minimal_parkingprice(Configuration *cfg,
+                                                   PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING,
+                                                   int paymentOptionIndex=0);
+
+int CALCULATE_LIBRARY_API get_maximal_parkingprice(Configuration *cfg,
+                                                   PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING,
+                                                   int paymentOptionIndex=0);
+
+int CALCULATE_LIBRARY_API compute_product_price(Configuration const *cfg,
+                                                PERMIT_TYPE permitType = PERMIT_TYPE::SHORT_TERM_PARKING);
 
 CalcState CALCULATE_LIBRARY_API compute_price_for_parking_ticket(       // deprecated
                                             parking_tariff_t *tariff,