Table 3. Variables and sources

Category	Variable	Description	Source
Dependent variable	Number of passengers	Between South Korea and China,Between South Korea and Japan	Korea Airports Corporation,Incheon International Airport Corporation
	Cargo volume
Explanatory variable	GDP	Gross domestic product	World bank
	PERGDP	Per capita GDP	World bank
	Exchange rate	Currency exchange rate of the country	OECD
	Oil price	International oil price	OECD, Statista