System Response
Prices must be available in or converted to the same currency(reference currency) so that a final total (prices of all attendee'sbookings) can be created.
The reference currency is the currency specified in the programparameters. If the 'currency' parameter was not completed when theprogram was started, the system will take the most frequently usedcurrency as reference currency.
Prices that cannot be converted will NOT be included in thetotal.

Procedure
Maintain the relevant exchange rate.