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Cited by 1,002Economic Growth and ProductivityFirm Innovation and GrowthInnovation Diffusion and Forecasting

Are Ideas Getting Harder to Find?

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Bloom, Nicholas, Jones, Charles I., Van Reenen, John, Webb, Michael·2020·American Economic Review
DOI 10.1257/aer.20180338
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Abstract

Long-run growth in many models is the product of two terms: the effective number of researchers and their research productivity. We present evidence from various industries, products, and firms showing that research effort is rising substantially while research productivity is declining sharply. A good example is Moore’s Law. The number of researchers required today to achieve the famous doubling of computer chip density is more than 18 times larger than the number required in the early 1970s. More generally, everywhere we look we find that ideas, and the exponential growth they imply, are getting harder to find. (JEL D24, E23, O31, O47)

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Authors
Bloom, N., Jones, C. I., Van Reenen, J., & Webb, M.
Affiliations
  • National Bureau of Economic Research (US)
  • Stanford University (US)
  • Department of Economics, MIT, LSE, and NBER (email: )
ORCID
Bloom, Nicholas
Venue
American Economic Review
Publisher
American Economic Association
Published
2020-04-01
Volume
110
Issue
4
Pages
1104-1144
ISSN
0002-8282 (ISSN-L)
DOI
10.1257/aer.20180338
OpenAlex
W2750722266
Cited by
1,002
References
50
Citations by year
2026: 203 · 2025: 176 · 2024: 168 · 2023: 149 · 2022: 122 · 2021: 90 · 2020: 54 · 2019: 20 · 2018: 11 · 2017: 5 · 2016: 3 · 2014: 1
FWCI
88.23
Type
journal article
Language
en
Open access
Locations
  • American Economic Review (publishedVersion)
  • RePEc: Research Papers in Economics (submittedVersion)
  • London School of Economics and Political Science Theses Online (London School of Economics and Political Science) (submittedVersion)
Funders
  • U.S. Department of Agriculture
  • National Institute of Food and Agriculture
  • National Agricultural Statistics Service
Topics
  • Social Sciences › Economics, Econometrics and Finance › Economics and Econometrics › Economic Growth and Productivity
  • Social Sciences › Economics, Econometrics and Finance › Economics and Econometrics › Firm Innovation and Growth
  • Social Sciences › Decision Sciences › Management Science and Operations Research › Innovation Diffusion and Forecasting
Keywords
research productivity, research effort, long-run economic growth, Moore's law, idea generation, technological progress

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