VAIM: value added imports, in 4 dimensions(import regions, source sectors, source regions, years).
Notation: the import region is where value added is finally absorbed in, it is also the destination region in VAEX.In WIOD 2013, there are 35 sectors and 41 regions. In addition to the 35 sectors, there are 5 aggregated levels results (Total, goods, manufacture, all service and some services related to production).