Patterns of Changes in Job Structure Project

Estonian translation by Sonja Kulmala available at:
Latvian translation by Arija Liepkalnietis available at:

Polish translation by Maria Stefanova. available at:

Research Objectives
This project examines the patterns of transformation of employment structures in developed capitalist countries in the last half of the 20th century, with special emphasis on the extent to which changes in employment structures generate jobs of different "quality". In particular we are concerned with the extent to which in the current period the pattern of job creation is polarized: good jobs and bad jobs are growing much faster than jobs in the "middle" of the employmdent structure.

The first phase of the research focused on the quality of jobs generated in the United States during periods of job expansion from the 1960s through then 1990s. The central results of this research are: First, the long 1990s economic boom produced a pattern of asymetrically polarized job expansion: very strong expansion of jobs in the top tier of the employment structure combined  with very limited growth in the middle.  Second, while job growth at the top was strong in the 1990s, the overall pattern of job expansion was much less favorable for the labor force as a whole than in earlier expansions. Third, there has been a dramatic change in the racial and gender patterns of job expansion since the 1960s: gender differences in job expansion were very sharp in the 1960s and quite muted in the 1990s, while the racially polarized character of job expansion has increased, especially at the bottom of the employment structure. Finally, immigration, especially of Hispanics, is deeply connected to the employment expansion in the bottom tiers of the employment structure. Underlying these descriptive patterns are dramatic changes in the sectoral patterns of job expansion in the 1990s compared to the 1960s: the much slower growth of middle-level jobs in the 1990s is rooted in the decline of manufacturing; the stronger growth of bottom end jobs is rooted in accelerated growth of retail trade and personal services in the 1990s; and the very strong growth of high end jobs is rooted in high tech sectors.

The next phase of this project will build on this research in three principle ways: (1) It will extend the research backwards to 1950 using different data from that in the original project; (2) It will expand the project comparatively, by examining patterns of job expansion in those developed economies for which comparable data are available; (3) It will use the leverage of the comparative framework to examine a variety of macro-structural explanations for variations in these patterns over time and across countries. Of particular interest will be the extent to which patterns of state regulation of labor markets and other economic variables, influence patterns of employment expansion. I will also examine the extent to which sectoral patterns of productivity growth, exposure to international competition and unionization rates might account for variations in the patterns of job growth.

A note on method of analysis
This project revolves around describing and explaining variations in patterns of job growth. A key methodological problem is defining how “jobs” will be differentiated in the analysis, and then how the patterns of growth among jobs so defined will be measured. The method used in the project involves creating a large occupation-by-sector employment matrix for the paid labor force in which the cells in this matrix define the different kinds of jobs in the economy. For the 1990s in the US, for example, a 104-occupation by 23-sector matrix was created, which yielded over 2000 different kinds of jobs. Examples of job-types at this level of disaggregation are janitors in business repair services; bus and truck drivers in retail trade; secretaries and typists in durable manufacturing; and financial managers in wholesale trade. These 2000+ jobs were then rank-ordered by the median hourly earnings of people in the job. These within-job earnings medians can be interpreted as an index of the earnings-potential of each kind of job (i.e. each cell in the occupation-by-sector matrix). Once the 2000+ jobs are ranked in this way, the patterns of job growth across this distribution could be studied. Thus, for example, in the 1990s in the US, 35% of all job expansion occurred in the top quintile of this job distribution, 22% occurred in the bottom quintile, but only 6% occurred in the middle quintile.

One of the advantages of this method is that variations across time and place in the fine-grained details of occupation and sector classifications systems do not substantially affect the results. That is, in order to ask the question of the form “what percent of total job growth occurs in the top quintile of the rank-ordered job distribution” (as defined above), all that we need is a rank ordering of the cells of an occupation by sector matrix. Small differences in the classification systems of occupations and sectors used to construct this matrix will have only marginal effects on the observed patterns. Given that in cross-national comparisons, as well as analyses over time in any single country, classification systems change frequently, this facilitates the analysis greatly.

Publications from the project

The American Jobs Machine: the trajectory of good and bad jobs in the 1960s and 1990s," (with Rachel Dwyer), Boston Review, December 2000
   Technical Appendix (HTML)

"The patterns of job expansions in the USA: a comparison of the 1960s and 1990s" (with Rchel Dwyer) Socioeconomic Review 2003, 1: 289-325.
Appendix to "The Patterns of Job Expansions in the United States:  a comparison of the 1960s and 1990s", by Erik Olin Wright and Rachel Dwyer

"Growing Apart: The “New Economy” and Job Polarization in California, 1992–2000"
by Ruth Milkman and Rachel Dwyer, Pp. 3-35 in The State of California Labor.  (Berkeley, CA: University of California Press.)