The travel balance of payments, calculated quarterly for the central bank of Austria (OeNB), compares the expenditure of nationals on travel abroad with the receipts of foreigners at home. The most important breakdown is the separate presentation of expenditure according to business and private reasons. The travel concept underlying the quarterly calculation goes beyond the tourism concept by taking into account the expenditure of all travellers, meaning also crossing of borders for non-tourist reasons. This includes expenditure in the course of regular shopping trips by residents close to the border, commuters, seasonal workers and students. All expenditures by daily and transit travellers are also included. As this is a hybrid statistic, no direct surveys of travellers are carried out for the purpose of compiling the statistics, but relevant tourism and travel statistics are combined into an overall system.