Input-output analytics for urban systems: explorations in policy and planning

Modelling complex systems like cities requires a theory of how elements interact (e.g. how transport influences trade, how education and housing impact labour, etc.), tempered by the tractability of measurements and assumptions. Combining the 2017 national UK Input-Output accounting table with local population and sector employment tallies from the Office of National Statistics (ONS), we develop an Multi-Regional Input-Output model with a novel spatial-interaction transport cost component to estimate trade between 48 UK cities and their Gross Domestic Products (GDPs). We extend the model to estimate future scenarios via ONS population projections over a constant national GDP growth of 2% per year. Without external shocks, our results reflect the so-called ‘North-South divide’: while northern UK cities may have higher GDPs than many southern cities (excluding London), their economic output per employee is lower. Our results suggest the prominence of lower value-added sectors like ‘Production’ in northern cities may account for lower income per worker, relative to the dominance of higher value-added sectors like ‘Financial and insurance’ and ‘Professional and support activities’ in southern cities.