Why Urban Productivity Premiums Are Up to 50% Larger Than Previously Estimated
Ahlfeldt, Heblich, Seidel & Yin: "The Price of Productivity" CRC Discussion Paper No. 563
Economists have long recognized that urban density fuels productivity, yet the measurement of these “agglomeration effects” has remained incomplete due to a historical focus on labor markets. In “The Price of Productivity,” authors Gabriel Ahlfeldt (HU Berlin), Stephan Heblich (University of Toronto), Tobias Seidel (University of Duisburg-Essen), and Fan Yin (HU Berlin) introduce a novel micro-geographic commercial rent index for Germany to investigate how productivity advantages capitalize into floor space prices. By developing a specific locally weighted regression approach to address the scarcity of commercial transaction data, the research provides a continuous price surface across the country’s local labor markets.
The findings offer a significant new perspective on the internal structure of cities. In large urban centers, commercial rents decline sharply by approximately 17% per kilometer from the central business district (CBD). This decay is notably steeper than the 13% decline observed in residential rents, indicating that the benefits of agglomeration are most intensely concentrated at the urban core. Furthermore, the analysis reveals that commercial rents at the CBD rise steeply with city population, exhibiting an elasticity of 15%.
The core contribution of this research lies in its refinement of total factor productivity (TFP) estimates. Traditional urban economics typically relies on wage data to measure the productivity premium of cities, finding a city-size elasticity of about 2% to 4%. However, this study demonstrates that firms pay for access to productive environments not only through higher wages to attract talent but also through higher rents for scarce floor space. When these commercial rents are factored in, the capitalization of productivity into floor space implies an additional agglomeration elasticity of TFP of approximately 2%.
Combining these channels reveals that the overall agglomeration elasticity of TFP is between 4% and 6%. This suggests that studies focusing solely on wages may be underestimating the true productivity benefits of large cities by one-third to one-half. These results have substantial implications for quantitative urban modeling and economic policy. If the productivity advantages of spatial concentration are greater than previously assumed, then land-use regulations that restrict the supply of floor space in high-density areas may cause larger efficiency losses than current models suggest. Ultimately, the research provides a unified framework for understanding how productivity is priced into urban environments, revealing that the true value of being in a city is far higher than what is reflected in paychecks alone.
Link: The Price of Productivity
