The Role of Urban Agglomerations for Economic and Productivity Growth

This article discusses how urban agglomerations – cities – affect economic productivity. It uses an internationally harmonized definition of cities that aims to capture the true extent of an urban agglomeration and is not limited by administrative city boundaries. It shows that labour productivity increases with city size. Among OECD metropolitan areas, agglomerations with more than 500,000 inhabitants, a 1 per cent population increase is associated with a 0.12 per cent increase in average labour productivity. Partly, this is explained by “sorting” as more productive workers tend to live in bigger cities. But bigger cities provide additional “agglomeration economies” to those working in them. Comparable workers are 0.02-0.05 per cent more productive in cities with a 1 per cent larger population. These differences compound to significant differentials, e.g. a similar worker in Madrid (6 million inhabitants) is, on average, nearly 15 per cent more productive than a worker in Toledo (120,000 inhabitants). Furthermore, the paper also shows that cities affect economic performance beyond their boundaries. Since 1995, per capita GDP growth in regions within 90 minutes driving of a large urban agglomeration has been approximately 0.4 percentage points higher than in those with no large urban agglomeration within 300 minutes of driving.