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Industry-level Productivity and International Competitiveness Between Canada and the United States (2001)

Editors: Dale W. Jorgenson and Frank C. Lee

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The purpose of this monograph is to illuminate the economic interrelationships between Canada and the United States. In order to achieve this objective, we have presented detailed comparisons of productivity trends and levels of output, input, and productivity for individual industries in the two countries. These comparisons employ purchasing power parities for both outputs and inputs and use a common methodology. While the estimates are preliminary in character, they embody the best information currently available on the determinants of relative standards of living and economic growth in both countries.

This monograph reflects the views of the authors, but not necessarily those of Industry Canada or of the institutions the authors are affiliated with. We would like to express our appreciation to Statistics Canada, the U.S. Bureau of Labor Statistics (BLS) and the Bureau of Economic Analysis (BEA) for data accessibility and consultations. In particular, the authors are grateful to Katharine Kemp of Statistics Canada for providing bilateral commodity price data, and Bruce Grimm and Dave Wasshausen of the BEA for details on the BEA investment data and prices.

We are grateful to Bob Arnold of CBO for helpful comments and discussions of the CBO's results and methods. We thank Erwin Diewert (University of British Columbia), Steve Oliner (Federal Reserve Board), Dan Sichel (Federal Reserve Board), and seminar participants at the Federal Reserve Bank of New York for helpful comments and discussions on Chapter 2. Dave Fiore provided excellent research assistance for Chapter 2. We are also indebted to Erwin Diewert (University of British Columbia), René Durand (Industry Canada), Rick Harris (Simon Fraser University), Jeremy Rudin (Finance Canada), Larry Rosenblum (U.S. Bureau of Labor Statistics) for their helpful comments on Chapters 3, 4 and 5. In addition, we thank Masahiro Kuroda (Keio University) and Kun-Young Yun (Yonsei University) for helpful discussions.

Last but not the least, we wish to thank Serge Nadeau and Someshwar Rao at Industry Canada for their unwavering support throughout the duration of the project. In addition, we also thank Denis Gauthier who supported this project at the inception. However, the authors are solely responsible for any remaining errors and omissions.


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One of the principal economic policy objectives shared by Canada and the United States is maintaining high and growing standards of living. Both countries have been remarkably successful at this and stand at the top of the world rankings in terms of economic performance. The first objective of this monograph is to quantify the sources of economic growth at the industry level in Canada and the United States. The second objective is to assess the relative competitiveness of American and Canadian industries.

In Chapter 2, Jorgenson and Stiroh focus on the recent revival of U.S. economic growth. They attribute the rise in the rate of U.S. economic growth since 1995 to a surge of investment in computers, software, and communications equipment and to a jump in the growth rate of total factor productivity (TFP). Average labour productivity (ALP) grew 0.95 percent per year more rapidly during 1995-98 than during 1990-95. More rapid TFP growth contributed 0.72 percent per year, while capital deepening generated 0.34 percent per year. These increases offset a modest decline in the rate of improvement of labour quality as the pool of available workers was exhausted.

In Chapter 3, Wulong Gu, Frank Lee and Jianmin Tang also adopt the constant quality indices of capital and labour inputs used in Chapter 2 for each of the 122 industries studied in Canada. The extent of asset types is not as detailed as that in the United States. They only consider five asset types — machinery and equipment (M&E), building structures, engineering structures, land and inventories. However, on the labour input side, workers are cross-classified by two sexes, three employment classes, seven age groups and four educational groups, for a total of 168 types. At the aggregate level, the same framework is adopted by aggregating the capital stock across different asset types and hours worked across different types of workers.

The results show that the Canadian private business sector's output growth slowed down from an annual rate of 5.6 percent during 1961-73 to 3.3 percent during 1973-88, and to 1.5 percent during 1988-95. TFP growth accounted for about 46 percent of output growth during 1961-73, and for 22 percent and 26 percent, respectively, during 1973-88 and 1988-95. At the same time, over 80 percent of the slowdown in output growth observed from the first to the second period is attributable to the slowdown in TFP growth. On the other hand, over 80 percent of the slowdown in output growth from 1973-88 to 1988-95 originated from the slowdown in the growth of both capital and labour inputs. The slowdown in the growth of capital stock and hours worked was mainly responsible for the input growth slowdown between the last two periods.

For a majority of the 122 industries examined in this chapter, input growth was a dominant source of output growth during 1961-73 and 1973-88. However, during 1988-95, TFP growth accounted for more than half of output growth in slightly more than half of these industries, primarily because input growth slowed down more than productivity growth between 1973-88 and 1988-95.

In Chapter 4, Wulong Gu and Mun Ho compare output growth between Canada and the United States in 33 industries. They first aggregate capital input in both countries to four asset types (M&E, structures, land and inventories) so that the underlying data used in the study are comparable. The authors do not use the U.S. data that incorporate the latest benchmark revision in the U.S. National Income and Product Accounts for the purpose of comparing the United States with Canada. The extensive benchmark revisions made in the United States have not yet taken place in the Canadian National Income and Product Accounts.

The results show that average growth rates of output in Canada were higher than in the United States for almost all industries before 1988. After 1988, output growth in Canada has been slightly lower than in the United States. On the productivity side, there was a substantial catch-up by Canadian industries to the productivity levels of U.S. industries during the period 1961-73. After 1973, productivity in Canadian industries grew at a rate similar to that of U.S. industries. Input growth is identified as the dominant source of output growth at the sectoral level, with productivity growth contributing about 20 percent of output growth for both countries during the entire period.

In the last chapter, Frank Lee and Jianmin Tang focus on international competitiveness between Canadian and U.S. industries. They first construct Canada-U.S. bilateral purchasing power parities for outputs and inputs by industry using bilateral Canada-U.S. commodity price data following Jorgenson and Introduction Kuroda (1995). In 1995, more than half of Canadian industries were more competitive than their U.S. counterparts. However, the competitive position of Canadian industries is threatened by higher capital input prices and lower TFP levels. Canada had higher capital input prices than the United States in 27 of the 33 industries, whereas Canada had lower TFP levels than the United States in 23 of the 33 industries. Unlike capital input prices, all Canadian industries had an advantage over their U.S. counterparts in terms of labour costs. Finally, most Canadian industries paid almost the same price for their intermediate inputs as their U.S. counterparts.


Baily, Martin Neil and Robert J. Gordon. "The Productivity Slowdown, Measurement Issues, and the Explosion of Computer Power." Brookings Papers on Economic Activity, 2 (1988): 347–420.

Blinder, Alan S. "The Speed Limit: Fact and Fancy in the Growth Debate." The American Prospect, 34 (September-October 1997): 57–62.

Brynjolfsson, Erik and Chris F. Kemerer. "Network Externalities in Microcomputer Software: An Econometric Analysis of the Spreadsheet Market." Management Science, 42, 12 ( December 1996): 1627–47.

Brynjolfsson, Erik and Shinkyu Yang. "Information Technology and Productivity: A Review of the Literature." Advances in Computers, 43 ( February 1996): 179–214.

Bureau of Economic Analysis. Fixed Reproducible Tangible Wealth of the United States, 1925–96, NCN-0136, May 1998a.

line. "Fixed Reproducible Tangible Wealth in the United States: Revised Estimates for 1995–97 and Summary Estimates for 1925–1997." Survey of Current Business, September 1998b, pp. 36–45.

line. Investment Estimates of Fixed Reproducible Tangible Wealth, 1925–1997. 1998c.

line. "National Accounts Data – Data from the Latest GDP Release.", 1999.

Bureau of Labor Statistics. Capital Stock Estimates for Input-Output Industries: Methods and Data, Washington (DC): Government Printing Office Bulletin 2034, Washington (DC): Government Printing Office, 1979.

line. Trends in Multifactor Productivity, 1948–1981, Washington (DC): Government Printing Office, 1983.

line. Labor Composition and U.S. Productivity Growth, 1948–1990, Bulletin 2426, Washington (DC): Government Printing Office, 1993.

line. BLS Handbook of Methods, Washington (DC): Government Printing Office, 1997.

line. Multifactor Productivity: Revisions to Capital Inputs for the BLS Multifactor Productivity Measures, Washington (DC): Government Printing Office,1998.

line. Multifactor Productivity Trends. USDL 99-36, February 11, 1999.

line. Productivity and Costs: Preliminary Fourth Quarter and Annual Averages, 1999. USDL 00-37, February 8, 2000.

Christensen, Laurits R. and Dale W. Jorgenson "Measuring Economic Performance in the Private Sector," in The Measurement of Economic and Social Performance. Edited by Milton Moss. New York: Columbia University Press, 1973, pp. 233–38.

Christensen, Laurits R., Dale W. Jorgenson, and Lawrence J. Lau. "Conjugate Duality and the Transcendental Logarithmic Production Function." Econometrica, 39, 4 ( July 1971): 255–56.

line. "Transcendental Logarithmic Production Function." Review of Economics and Statistics, 55 (1973): 28–45.

Cole, Roseanne, Y. C. Chen, Joan A. Barquin-Stolleman, Ellen Dulberger, Hurhan Helvacian, and James H. Hodge. "Quality-adjusted Price Indexes for Computer Processors and Selected Peripheral Equipment." Survey of Current Business, 66, 1 ( January 1986): 41–50.

Congressional Budget Office. "CBO's Method for Estimating Potential Output." CBO Memorandum, October 1995.

line. "An Economic Model for Longrun Budget Simulations." CBO Memorandum, 1997.

line. The Budget and Economic Outlook: Fiscal Years 2000–2009. Washington (DC): Government Printing Office, January 1999a.

line. "The Budget and Economic Outlook: An Update." CBO Papers, July 1999b.

line. The Budget and Economic Outlook: Fiscal Years 2001–2010. Washington (DC): Government Printing Office, January 2000.

Corrado, Carol and Lawrence Slifman. "Decomposition of Productivity and Unit Costs." American Economic Review, Papers and Proceedings, 89, 2 ( May 1999): 328–32.

Council of Economic Advisors. The Annual Report of the Council of Economic Advisors, Washington (DC): Government Printing Office, 2000.

Dean, Edward R. "The Accuracy of the BLS Productivity Measures." Monthly Labor Review, February 1999, pp. 24–34.

Department of Commerce. The Emerging Digital Economy II, Washington (DC), June 1999.

Diewert, W. Erwin. "Functional Forms for Profit and Transformation Functions." Journal of Economic Theory, 6 (1973): 284–316.

line. "Aggregation Problems in the Measurement of Capital," in The Measurement of Capital. Edited by Dan Usher. Chicago: University of Chicago Press, 1980.

Diewert, W. Erwin and Denis A. Lawrence. "Progress in Measuring the Price and Quantity of Capital." Mimeo, University of British Columbia, 1999.

Domar, Evsey. "On the Measurement of Technological Change." Economic Journal, 71 (1961): 709–29.

Dougherty, J. Chrysostom. "A Comparison of Productivity and Economic Growth in the G-7 Countries." Ph.D. Dissertation, Harvard University, 1992.

Dougherty, J. Chrysostom and Dale W. Jorgenson. "There Is No Silver Bullet: Investment and Growth in the G7." National Institute Economic Review, 162 ( October 1997): 57–74.

Durand, René. "Aggregation, Integration and Productivity Analysis: An Overall Framework." Aggregate Productivity Measures, Statistics Canada, Cat. No. 15-204, July 1989.

line. "Transforming Input-output Tables for Productivity Analysis." Mimeo, Statistics Canada, 1998.

Federal Reserve Board. Balance Sheets for the U.S. Economy. Release C.9, June 1995.

line. Flow of Funds Accounts of the United States. Release Z.1, 1997.

Fisher, Franklin M. Aggregation – Aggregate Production Functions and Related Topics. Cambridge (MA): The MIT Press, 1992.

Fisher, Lawrence M. "New Era Approaches: Gigabyte Chips." New York Times, February 7, 2000, p. C8.

Flamm, Kenneth. "Measurement of DRAM Prices: Technology and Market Structure," in Price Measurements and their Uses. Edited by Murray F. Foss, Marilyn E. Manser, and Allan H. Young. Chicago: University of Chicago Press, 1993.

Fraumeni, Barbara. "The Measurement of Depreciation in the U.S. National Income and Public Accounts." Survey of Current Business, July 1997.

Gandal, Neil, "Hedonic Price Indexes for Spreadsheets and an Empirical Test for Network Externalities." RAND Journal of Economics, 25, 1 (Spring 1994): 160–70.

General Accounting Office. "The Deficit and the Economy: An Update of Long-term Simulations." GAO/AIMD/OCE-95-119, 1995.

line. "Deficit Reduction and the Long Term." GAO/T-AIMD-96-66, 1996.

Gordon, Robert J. The Measurement of Durable Goods Prices, Chicago: University of Chicago Press, 1990.

line. The Economics of New Goods, Chicago: University of Chicago Press, 1997.

line. "U.S. Economic Growth Since 1870: What We Know and Still Need to Know." American Economic Review, Papers and Proceedings, 89, 2 ( May 1999a): 123–28.

line. "Has the 'New Economy' Rendered the Productivity Slowdown Obsolete?" Manuscript, Northwestern University, June 12, 1999b.

Greenwood, Jeremy, Zvi Hercowitz, and Per Krusell. "Longrun Implications of Investment Specific Technological Change." American Economic Review, 87, 3 (1997): 342–63.

Griliches, Zvi. "The Search for R&D Spillovers." Scandinavian Journal of Economics, 94 (1992): 29–47.

line. "Productivity, RD, and the Data Constraint." American Economic Review, 84, 1 ( March 1994): 1–23.

Griliches, Zvi and Dale W. Jorgenson. "Sources of Measured Productivity Changes: Capital Input." American Economic Review, 56 ( May 1966): 50–61.

Grimm, Bruce T. "Quality Adjusted Price Indexes for Digital Telephone Switches." Bureau of Economic Analysis, unpublished memo, 1997.

Gullickson, William and Michael J. Harper. "Possible Measurement Bias in Aggregate Productivity Growth." Monthly Labor Review, February 1999, pp. 47–67.

Haimowitz, Joseph H. "Has the Surge in Computer Spending Fundamentally Changed the Economy?" Economic Review, Federal Reserve Bank of Kansas City, 2nd Quarter, 1998, pp. 27–42.

Hall, Robert E. "The Relation Between Price and Marginal Cost in U.S. Industry." Journal of Political Economy, 96,5 (1988): 921–47.

Hercowitz, Zvi. "The ‘Embodiment' Controversy: A Review Essay." Journal of Monetary Economics, 41 (1998): 217–24.

Ho, Mun S. and Dale W. Jorgenson. "The Quality of the U.S. Workforce, 1948–95." Mimeo, Harvard University, 1999.

Ho, Mun S., Dale W. Jorgenson, and Kevin J. Stiroh. "U.S. High-tech Investment and the Pervasive Slowdown in the Growth of Capital Services." Mimeo, Harvard University, 1999.

Hooper, Peter and Elizabeth Vrankovich. "International Comparisons of the Level of Unit Labor Costs in Manufacturing." International Finance Discussion Papers, 527, Board of Governors of the Federal Reserve System, 1995.

Hulten, Charles R. Total Factor Productivity: A Short Biography. NBER Working Paper 7471, January 2000.

Johnson, Joanne. "A KLEMS Database: Describing the Input Structure of Canadian Industry." Aggregate Productivity Measures, Statistics Canada, Cat. No. 15-204E, 1994, pp. 19–32.

Jorgenson, Dale W. "The Embodiment Hypothesis." Journal of Political Economy, 74, 1 (1966): 1–17.

line. "Productivity and Economic Growth," in Fifty Years of Economic Measurement. Edited by E. Berndt and J. Triplett. Chicago: University of Chicago Press, 1990.

line. "Empirical Studies of Depreciation." Economic Inquiry, 34, 1 ( January 1996): 24–42.

line ed. "Productivity and Postwar U.S. Economic Growth," in Productivity, Volume 1: Postwar U.S. Economic Growth, MIT Press, 1995a, pp. 1–23.

line. ed., "Productivity and Economic Growth," in Productivity, Volume 2: International Comparisons of Economic Growth, MIT Press, 1995b, pp. 1–98.

Jorgenson, Dale W., Frank Gollop, and Barbara Fraumeni. Productivity and U.S. Economic Growth. Harvard University Press, 1987.

Jorgenson, Dale W. and Zvi Griliches. "The Explanation of Productivity Change." Review of Economic Studies, July 1967.

Jorgenson, Dale W. and Masahiro Kuroda. "Productivity and International Competitiveness in Japan and the United States, 1960–1985," in Productivity, Volume 2, International Comparisons of Economic Growth. Edited by Dale W . Jorgenson, MIT Press, 1995.

Jorgenson, Dale W., Masahiro Kuroda, and Mieko Nishimizu. "Japan-U.S. Industry-level Productivity Comparisons, 1960–1979." Journal of the Japanese and International Economies, 1 ,1 (1987): 1–30.

Jorgenson, Dale W. and Mieko Nishimizu. "U.S. and Japanese Economic Growth, 1952–1974." Economic Journal, 88 ( December 1978): 707–26.

Jorgenson, Dale W. and Kevin J. Stiroh. "Computers and Growth." Economics of Innovation and New Technology, 3, 3–4 (1995): 295–316.

line. "Information Technology and Growth." American Economic Review, Papers and Proceedings, 89, 2 ( May 1999): 109–15.

line. "U.S. Economic Growth at the Industry Level." American Economic Review, Papers and Proceedings, May 2000.

Jorgenson, Dale W. and P. J. Wilcoxen. "Environmental Regulation and U.S. Economic Growth." The Rand Journal of Economics, 21, 2 (Summer 1990): 314–40.

Jorgenson, Dale W. and Eric Yip. "Whatever Happened to Productivity Growth? Investment and Growth in the G-7." in New Developments in Productivity Analysis. Edited by E. R. Dean, M. J. Harper, and C. Hulten, University of Chicago Press, 1999.

Jorgenson, Dale W. and Kun-Young Yun. Tax Reform and the Cost of Capital. Oxford: Clarendon Press, 1991.

Katz, Arnold J. and Shelby W. Herman. "Improved Estimates of Fixed Reproducible Tangible Wealth, 1925–95." Survey of Current Business, May 1997, pp. 69–92.

Katz, Lawrence F. and Alan B. Krueger. "The High-pressure U.S. Labor Market of the 1990s." Brookings Papers on Economic Activity, 1 (1999): 1–87.

Kemp, Katharine. International Price and Quantity Comparisons: Purchasing Power Parities and Real Expenditures, Canada and the United States. National Accounts and Environment Division, Technical Series Number 25, Statistics Canada, 1993.

Kiley, Michael T. "Computers and Growth with Costs of Adjustment: Will the Future Look Like the Past." Mimeo, Federal Reserve Board, July 1999.

Koumanakos, Peter, Richard Landry, Kuen Huang, and Susanna Wood. Canadian Net Capital Stock Estimates and Depreciation Profiles: A Comparison Between the Existing Series and a Test Series Using the U.S. (BEA) Methodology. Working Paper, Investment and Capital Stock Division, Statistics Canada, 1999.

Krugman, Paul. The Age of Diminished Expectations: U.S. Economic Policy in the 1990s. Cambridge (MA): MIT Press, 1990.

line. "How Fast Can the U.S. Economy Grow?" Harvard Business Review, 75, 4 (July-August 1997): 123–29.

Kuroda, Masahiro and Koji Nomura." Productivity and International Competitiveness." Mimeo, Keio University, 1999.

Lum, Sherlene K. S. and Robert E. Yuskavage. "Gross Product by Industry, 1947–96." Survey of Current Business, November 1997, pp. 20–34.

McGuckin, Robert H. and Kevin J. Stiroh. "Do Computers Make Output Harder to Measure?" Journal of Technology Transfer, forthcoming, 2000.

Moulton, Brent R., Robert P. Parker, and Eugene P. Seskin. "A Preview of the 1999 Comprehensive Revision of the National Income and Product Accounts, Definitional and Classification Changes." Survey of Current Business, August 1999, pp. 7–19.

OECD. International Sectoral Database. Paris, 1998.

Office of Management and Budget. Analytical Perspectives, Budget of the United States Government, Fiscal Year 1998. Washington (DC): Government Printing Office, 1997.

line. Analytical Perspectives, Budget of the United States, Fiscal Year 2001. Washington (DC): Government Printing Office, 2000.

Oliner, Stephen D. "Constantquality Price Change, Depreciation, and the Retirement of Mainframe Computers," in Price Measurement and Their Uses. Edited by Murray F. Foss, Marilyn E. Manser, and Allan H. Young. Chicago: University of Chicago Press, 1993, pp. 19–61.

line. Measuring Stocks of Computer Peripheral Equipment: Theory and Application. Board of Governors of the Federal Reserve System, May 1994.

Oliner, Stephen D. and Daniel E. Sichel. "Computers and Output Growth Revisited: How Big Is the Puzzle?" Brookings Papers on Economic Activity, 2 (1994): 273–334.

line. "The Resurgence of Growth in the Late 1990s: Is Information Technology the Story?" Mimeo, Federal Reserve Board, February 2000.

Parker, Robert and Bruce Grimm. "Software Prices and Real Output: Recent Developments at the Bureau of Economic Analysis." Paper presented at the NBER Program on Technological Change and Productivity Measurement, March 17, 2000.

Sichel, Daniel E. The Computer Revolution: An Economic Perspective. Washington (DC): The Brookings Institution, 1997.

line. "Computers and Aggregate Economic Growth." Business Economics, 34, 2 ( April 1999): 18–24.

Social Security Administration. Economic Projections for OASDI Cost and Income Estimates: 1992." Actuarial Study No. 108, SSA Pub. No. 11-11551, December 1992.

line. 1996 Annual Report of the Board of Trustees of the Federal Old-age and Survivors Insurance and Disability Trust Funds. Washington (DC): Government Printing Office, 1996.

Solow, Robert M. "Technology Change and the Aggregate Production Function." The Review of Economics and Statistics, 39 ( August 1957): 312–20.

line. "Investment and Technical Progress," in Mathematical Methods in the Social Sciences, 1959. Edited by Kenneth J. Arrow, Samuel Karlin, and Patrick Suppes. Stanford (CA): Stanford University Press, 1960.

line. "We'd Better Watch Out." New York Times Book Review, July 12, 1987.

Statistics Canada. Fixed Capital Flows and Stocks, 1961–1994 Historical. Catalogue No. 13-568, 1994a.

line. Aggregate Productivity Measures. Catalogue No. 15-204, 1994b.

line. Documentation for Micro Data File, Survey of Consumer Finance. Household Surveys Division, Ottawa, 1996.

line. Guide to the Labor Force Survey, Ottawa, 1997.

Stiroh, Kevin J. "Computers, Productivity, and Input Substitution." Economic Inquiry, 36, 2 ( April 1998a): 175–91.

line. "Longrun Growth Projections and the Aggregate Production Function: A Survey of Models Used by the U.S. Government." Contemporary Economic Policy, 16 ( October 1998b): 467–79.

line. "Is There a New Economy?" Challenge, July-August 1999, pp. 82–101.

Tevlin, Stacey and Karl Whelan. "Explaining the Equipment Investment Boom of the 1990s." Mimeo, Division of Research and Statistics, Federal Reserve Board, December 1999.

Triplett, Jack E. "The Economic Interpretation of Hedonic Methods." Survey of Current Business, 66, January 1986, pp. 36–40.

line. "Price and Technological Change in a Capital Good: A Survey of Research on Computers," in Technology and Capital Formation. Edited by Dale W. Jorgenson and Ralph Landau, Cambridge (MA): The MIT Press, 1989.

line. "High-tech Industry Productivity and Hedonic Price Indices." OECD Proceedings: Industry Productivity, International Comparison and Measurement Issues, 1996, pp. 119–42.

line. "Economic Statistics, the New Economy, and the Productivity Slowdown." Business Economics, 34, 2 ( April 1999): 13–7.

Triplett, Jack E. and Barry Bosworth. "Productivity in the Service Sector." Mimeo, The Brookings Institution, Washington (DC), January 2000.

Whelan, Karl. "Computers, Obsolescence, and Productivity." Mimeo, Division of Research and Statistics, Federal Reserve Board, December, 1999.

Williamson, W. Gordon and A. Craig Lahmer. Preparing Your Corporate Tax Returns, CCH Canadian Limited, 1996.

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