Table 2.

Explained variables included in research

	Indicators		Justification for the Choice
		Data base	Utilization of the variable in research (selected examples):
E&T group	National accounts aggregates by industry (Economic): Value added, gross Operating surplus and mixed income	European Commission; Eurostat Data Base: Economy and Finance, National Accounts (ESA 2010)	The economic effects of tourism, business development and in the context of sustainable and healthy tourism development to measure the tourism industry’s contribution and leakages (Boz 2011); tourism as a source of economic growth (Dwyer et al. 2009); digital transformation and its influence on GDP (Mićić 2017); the impact of digital development on the tourism industry as a function of GDP (Watkins et al. 2018)
	Annual detailed enterprise statistics for services (Tourism) Enterprises–number Turnover or gross premiums written Number of establishments, bedrooms and bed-places Arrivals at tourist accommodation establishments	European Commission; Eurostat Data Base: Industry Trade and Services, Tourism	Variables considered in the context of welfare of individuals, household income, employment, private revenue etc. and also an increase in government revenue (FaladeObalade and Dubey 2014); research on the impact of tourism infrastructure on the size of the tourism economy (Mesjasz-Lech 2017); studies on the empirical relationship between international tourism and the adoption of digital technologies (Lopez-Cordova 2020); the relationship between the number of companies and digitization and the number of enterprises and economic growth (Trașcă et al. 2019)
ICT group	Enterprises with internet access	European Commission; Eurostat Data Base: Science Technology Digital Society	Survey on the effects of the digital economy on the tourism industry through Internet and Web technologies (Hojeghan and Esfangareh 2011); (Adamczewski 2016)
	Websites and functionalities: Enterprises where the website had online ordering, reservation or booking and at least one of: webacc, webctm, webot or webper		Identifying and developing ICT tools for tourism innovation (Mićić 2017); the use of diverse ICTs has a positive effect on market share and economic growth (López and Aramendia-Muneta 2013); ICT as an innovative approach to managing sustainable tourism development (Ali and Frew 2014)
	E-commerce sales A minimum of 1% of turnover generated from online sales	European Commission; Eurostat Data Base: Sustainable development indicators	The impact of e-commerce on development (Ying 2017); the impact of e-commerce on profitability and sustainability (Elhaj and Barakeh 2015) (Hojeghan and Esfangareh 2011);
SDGs group	Promote sustained, inclusive and sustainable economic growth, full and productive employment and decent work for all: Real GDP per capita (economic and sustainability)		It is recognized that for the tourism economy, and especially for safe and active leisure, factors such as inland water bathing sites with excellent water quality, peaceful and inclusive societies without conflicts or incidents affecting security, accountable and inclusive institutions at all levels and climate action are important. The European Commission, through Eurostat, is analyzing the impact of these factors in various cross-sections of sustainability. They were also studied in the context of the tourist economy (Marttunen et al. 2019) (Frone and Frone 2013) (Kovari and Zimanyi 2011) (Brondoni 2016) (Eijgelaar et al. 2010)
	Ensure the availability and sustainable management of water and sanitation for all: Inland water bathing sites with excellent water quality
	Promote peaceful and inclusive societies for sustainable development, provide access to justice for all and build effective, accountable and inclusive institutions at all levels: General government total expenditure on law courts
	Climate action: Greenhouse gas emissions

Source: own elaboration