What is a footprint analysis? | The three-step pipeline | Concepts and terminology | Supply-use tables and process groups | Mixed units in the supply-use system | Bilateral trade | Commodity balance sheets (CBS) | The Z matrix (inter-industry flows) | Trade shares | The Y matrix (final demand) | The X vector (total output) | FABIO adjustments | The Leontief inverse (L) | Environmental extensions | The footprint | Running the analysis | Step 1: Build the IO model | Step 2: Compute the Leontief inverse | For large systems | Step 3: Compute the footprint | Dense path (pre-computed L, small systems) | Using Z directly (large systems) | With and without fd_labels | Analysing the results | A conservation check | Processing multiple years | Parallel execution (optional) | Summary | References