## 5 Conclusions  
In order to reduce greenhouse gas emissions, global consumption of NG has been increasing while the use of coal has been decreasing. In addition, NG is expected to act as a bridge energy in the move toward a carbon-neutral era. This study attempted to identify the impact of production or investment in the NG supply sector on the national economy using IO analysis. The area to be analyzed was not limited to South Korea only, but Japan, which imports most of the NG and has similar conditions to South Korea in terms of being an energy island, was also included. This study analyzed and compared the respective production-inducing effects, value-added creation effects, wage-inducing effects, employment-inducing effects, supply shortage effects, and price-inducing effects of NG supply sector in South Korea and Japan, using the most recent IO table. The main results of this study are as follows. It was found that the production-inducing, value-added creation, and employment-inducing effects of an investment of USD 1 billion in the NG supply sector on the entire national economy were greater in Japan than those in South Korea. On the other hand, the wage-inducing effects of an investment of USD 1 billion in the NG supply sector were greater in South Korea than in Japan. In addition, both the supply-shortage effect and the price-inducing effect of the NG supply sector are greater in South Korea than in Japan. The results of this study can be useful information when the government establishes policies related to NG import and supply in the future. For example, liberalization of the domestic LNG market can be considered to improve the production-inducing effect and value-added creation effect of the NG supply industry. In addition, a management system should be established in preparation for NG supply disruptions. Additional measures for stable NG supply can be reviewed for industries that have a significant supply-disruption effect in the NG industry. In addition, the results of this study can contribute to practitioners and society in South Korea. For example, rising international NG prices, increase of labor costs, and environmental regulations can cause domestic NG prices to rise. The results of this study can be useful in predicting the impact of the price increase in advance. In particular, because NG price effects are presented separately for each industry sector, it is possible to identify which sectors are more or less affected. Furthermore, if the market size of the NG supply industry is predicted, the size of the economic effect can be anticipated based on the size. In other words, because the production-inducing effect of KRW 1 of production or investment in the NG supply industry on the national economy is KRW 1.07919, if the market size grows by KRW 500 billion, it is expected to bring about a total production-inducing effect of KRW 539.60 billion for the entire country. The authors attempt to mention four more things about the implications of the analysis results. First, the various economic effects presented above have their own potential uses. Therefore, it is difficult to judge whether one economic effect is more or less important than another. For example, it cannot be said that the price-pervasive effect is more important or less important than the wage-inducing effect. The price-pervasive effect only means how much a price change in the NG supply sector changes prices in other sectors, and the wage-inducing effect only means how much investment or production in the NG supply sector results in wages in other sectors. Second, although a comparative analysis was conducted in this study, it cannot be judged that one country's NG supply sector is superior or inferior to another country's NG supply sector. The previously reported analysis results only indicate the characteristics and role of a country's NG supply sector.