Secular change of interdependencies in the clusters of the Japanese motor vehicle industry: a case study in the Tokai region

The Tokai region, including the prefectures of Aichi, Shizuoka, Mie, Gifu, and Shiga, in the center of Japan’s largest island, Honshu, houses clusters of the motor vehicle industry (MVI) and accounts for more than 50% of the domestic value from the MVI’s manufactured goods shipments. The subcontracted factories in the MVI tend to locate their main hub close to the assembly factories, creating large supply-chain structures with wide transactions. Since the 1990s, new automotive assembly factories and subcontracted factories have been built outside Aichi, in the Kyushu and Tohoku regions. This may have had an influence on local industries and economy. This study applies the hypothetical extraction method to the Tokai region using the Chubu-region multi-regional input–output tables to understand the secular changes of interdependencies in the MVI as each prefecture in the Tokai region has automotive assembly factories. The study shows that the Aichi MVI has strengthened its ties with industries in other prefectures in the Tokai region and elsewhere because the rate of growth for Aichi dropped from 2005 to 2010. Still, other prefecture rates rose, thus expanding its supply-chain structure throughout Japan more than before. In addition, the study shows that the Shizuoka MVI has increased business relationships not only within its region but also with Aichi. These results highlight that the industrial linkage between the Aichi MVI and the Shizuoka MVI has deepened. However, the results show that the supply-chain structures of the Mie, Gifu, and Shiga MVI have remained inside of their respective regions.