4. Data and resultsThe study applied the methodology of the ML index by Chung et al. to three periods of panel data for 45 luxury hotels obtained from the official data published for 2003, 2005 and 2007 (AORITH, 2003, 2005, 2007; Chung et al., 1997). All luxury hotels are either 4- or 5-star hotels. The total count of international tourist hotels is more than 45 for 2005 and 2007; only 45 international tourist hotels have complete panel data for the three periods 2003, 2005 and 2007. According to our study, more than half of them are five-star hotels. In addition, the official hard copy publications include the respective affiliated hotel chains and their contracted years.