Origin Market Tourist Board Insights | Australia

Tourism Australia 

https://www.tourism.australia.com/en/markets-and-stats/tourism-statistics.html 

Several statistical, infographic and research options are available, including detailed data on both domestic and international tourism to the country and the aviation market along with sentiment trackers for both international travellers and those who live in Australia. 

Plenty of evidence regarding the economic importance of tourism is made available, along with a guide that describes the various agencies in Australia that release tourism statistics.