National commodity-industry investment bridge matrix: A simplified standard approach

The renewed focus on industrial policy underscores the need for greater detail on gross capital formation, particularly by linking investing industries to capital goods and supplying industries. The technical note presents a simple yet empirically sound method for estimating a commodity-industry investment bridge matrix, designed for integration into supply and use tables. The approach follows standard methodologies from input-output system manuals. Relying on a limited set of accounting data, the method ensures consistency in investment volume and structure while identifying detailed commodity-industry relationships. An RAS balancing algorithm adjusts the initial estimate iteratively, respecting margin constraints. Finally, the investment bridge matrix is reclassified into an industry-by-industry matrix using the market share matrix derived from the supply table, enabling its incorporation into symmetric input-output tables. The procedure was developed specifically for the Italian economy.