First in the study, some inter-country input-output tables (ICIOs) that can be publicly available have been searched. As a result, it was decided to use WIOD (the World Input-Output Database) which have been published recently under the EU's fund. This paper is an analysis that focused on the construction industry, which is one of the 35 industrial sectors in the WIOD. There are two main contents in this paper. First one is to find the total amount of production value of the national & international construction industry. The second is an analysis of the industry's input structure in construction production, which can be measured by the ratios of materials, services and labors from home and abroad. This paper revealed the following points.
· The total production value of the world's construction industry in 2011 is 10,410 million US$ (837.1 trillion yen), and the nominal value is increasing year by year. Taking the ratio of the total production value of the whole world, it has remained stable and in a range of 6.80 to 7.52% (in 1995-2011 years). (see Table 2)
· In comparison of country-specific construction industry total production value of China in 2011 is 20.2% of the world's total, followed by the United States is 10.2%, Japan accounted for 7.1%. (see Fig. 4)
· In every country, the size of gross value added in the total production is different. Brazil, Lithuania and the United States are as high as 50%, on the contrary, China and Taiwan are lower value of exceed 20%. (see Fig. 5)
· In a cluster analysis based on the configuration ratio of the input structure, for example, the three countries such as China, Taiwan and South Korea, have become clear that there is a large difference from other countries. It is suggested that the terms of the geographical proximity and the size of the construction investment has been affected to the classification result. (see Fig. 7)
· As for the ratio to procure construction materials and services only within the country (the domestic sufficiency rate), China has the highest 94.9%, so, the country is dependent only 5.1% in foreign countries. On the other hand, Malta depends on foreign countries in the ratio of 49.4%. There is a trend that the higher the total production value, the higher the domestic sufficiency ratios. (see Table 3)
In one country's National I-O tables (NIOT), foreign sections are aggregated into one. On the other hand, the ICIO clearly recognize foreign countries and the breakdown trade value of them are concretely expressed. The WIOD tables are as such, and it is possible to pick up the national and/or international business relationships between industries. Fortunately, the “construction industry” can have a common recognition between countries according to the ISIC industrial classification system. So, each country's national statistics and the WIOD tables have also been created consistently. Therefore, the scope of "construction industry" which is the main interest of the study can have a unified recognition between multiple countries.
Although this paper clearly stated the difference of contents and features of the industry, it is difficult to explain the reasons clearly. If the "construction industry" could be subdivided into architectural sector and civil engineering sector, for example, it would be more beneficial for concise comparison. That is one of the limits in the WOID as for an analytical tool. It will need to step into a wide range analysis on other data, or narrow down the target countries will also needed.
This paper focused on the input structure of the industry. In the next, similar analysis of the production structure will be performed.
