The industrial sector of Thailand has been divided into nine sub-sectors, namely the food and beverage sub-sector, the textiles sub-sector, the wood and wood products sub-sector, the paper and pulp sub-sector, the chemical and petrochemical sub-sector, the non-metallic sub-sector, the basic metal sub-sector, the fabricated metal sub-sector and other miscellaneous sub-sector, based on economic reporting procedures [39]. In this study, the nine sub-sectors are assumed to be independent of each other.