diff --git a/library/src/calculator_functions.cpp b/library/src/calculator_functions.cpp
index d9cd1e9..3616b9d 100644
--- a/library/src/calculator_functions.cpp
+++ b/library/src/calculator_functions.cpp
@@ -350,30 +350,28 @@ std::string Calculator::GetDurationFromCost(Configuration* cfg,
 /// <inheritdoc/>
 ///
 
-uint32_t Calculator::GetCostFromDuration(Configuration const* cfg,
+uint32_t Calculator::GetCostFromDuration(Configuration *cfg,
                                          QDateTime const &start,
-                                         quint64 timeStepInMinutes,
-                                         uint8_t paymentMethod) {
+                                         quint64 timeStepInMinutes) const {
     // for instance, a tariff as used in Schoenau, Koenigssee: only steps, no
     // special days, nonstop.
-    if (paymentMethod == PaymentMethod::Steps
+    if (cfg->YearPeriod.size() == 0
      && cfg->SpecialDays.size() == 0
      && cfg->SpecialDaysWorktime.size() == 0) {
         QDateTime const end = start.addSecs(timeStepInMinutes*60);
-        return GetCostFromDuration(cfg, start, end, paymentMethod);
+        return GetCostFromDuration(cfg, start, end);
     }
     return 0;
 }
 
-uint32_t Calculator::GetCostFromDuration(Configuration const* cfg,
+uint32_t Calculator::GetCostFromDuration(Configuration * cfg,
                                          QDateTime const &start,
-                                         QDateTime const &end,
-                                         uint8_t paymentMethod) {
-    if (paymentMethod == PaymentMethod::Steps
+                                         QDateTime const &end) const {
+    if (cfg->YearPeriod.size() == 0
      && cfg->SpecialDays.size() == 0
      && cfg->SpecialDaysWorktime.size() == 0) {
         int const timeStepInMinutes = start.secsTo(end) / 60;
-        return GetPriceForTimeStep(cfg, paymentMethod, timeStepInMinutes);
+        return GetPriceForTimeStep(cfg, timeStepInMinutes);
     }
     return 0;
 }
@@ -386,12 +384,12 @@ uint32_t Calculator::GetCostFromDuration(Configuration const* cfg,
 /// <inheritdoc/>
 double Calculator::GetCostFromDuration(Configuration* cfg, uint8_t payment_option, const QDateTime start_datetime, QDateTime & end_datetime,  double durationMin, bool nextDay, bool prepaid)
 {
-    // condition for 'PaymentMethod::Steps' (e.g. 332/Schoenau):
-    if (cfg->SpecialDays.size() == 0
+    if (cfg->YearPeriod.size() == 0
+        && cfg->SpecialDays.size() == 0
         && cfg->SpecialDaysWorktime.size() == 0)
     {
         end_datetime = start_datetime.addSecs(durationMin*60);
-        return GetCostFromDuration(cfg, start_datetime, end_datetime, PaymentMethod::Steps);
+        return GetCostFromDuration(cfg, start_datetime, end_datetime);
     }
 
     // Get input date