January 2002

Investment-Specific Technical Change in the US (1947-2000): Measurement and Macroeconomic Consequences

Jason G. Cummins and Giovanni L. Violante

Abstract:

By extrapolating Gordon's (1990) measures of the quality-bias in the official price indexes, we construct quality-adjusted price indexes for 24 types of equipment and software (E&S) from 1947 to 2000 and use them to measure technical change at the aggregate and at the industry level. Technological improvement in E&S accounts for an important fraction of postwar GDP growth and plays a key role in the productivity resurgence of the 1990s. Driving this finding is 4 percent annual growth in the quality of E&S in the postwar period and more than 6 percent annual growth in the 1990s. The acceleration in the 1990s occurred in every industry, consistent with the idea that information technology represents a general purpose technology. Furthermore, we measure for the aggregate economy and different sectors the "technological gap": how much more productive new machines are compared to the average machine. We show that the technological gap explains the dynamics of investment in new technologies and the returns to human capital, consistent with Nelson and Phelps' (1966) conjecture. Since the technological gap continues to increase -- it more than doubled in the past 20 years -- our evidence supports the view that at least some of the recent increase in productivity growth is sustainable.

Keywords: Quality-adjusted prices, growth accounting, skill premium

PDF: Full Paper

Disclaimer: The economic research that is linked from this page represents the views of the authors and does not indicate concurrence either by other members of the Board's staff or by the Board of Governors. The economic research and their conclusions are often preliminary and are circulated to stimulate discussion and critical comment. The Board values having a staff that conducts research on a wide range of economic topics and that explores a diverse array of perspectives on those topics. The resulting conversations in academia, the economic policy community, and the broader public are important to sharpening our collective thinking.

Back to Top
Last Update: January 29, 2021