This paper applies recent advances in the study of labor market dynamics to a representative developing country with a large informal or unregulated sector, Mexico. It studies quarterly gross flows of workers over a 15-year period that includes two recoveries and recessions, including the celebrated 1995 Tequila crisis. It finds, first, that the formal or modern salaried sector shows the same procyclical job finding rate and mildly countercyclical separation behavior identified in the recent U.S. literature, and relative wage rigidity, both consistent with Shimer (2005a) and Hall (2005). The unregulated informal sector, however, shows reasonable acyclicality in the job finding rate coupled with sharp countercyclical movements in the job separation rate, consistent with standard small firm dynamics and Davis and Haltiwanger (1992 and 1999). This interaction of regulatory coverage and firm sizes, and patterns of gross worker flows thus sheds suggestive light on the roots of countercyclical job finding behavior in the U.S. literature. Second, the patterns of worker transitions between formality and informality correspond to the job-to-job dynamics observed in the United States and not to the traditional idea of informality constituting the inferior sector of a segmented market. That said, the countercyclical job finding in the formal sector combined with the acyclical job finding in informality does lead to the latter absorbing relatively more labor during downturns. Third, aggregate employment dynamics vary across the Tequila crisis and the later 2001 slowdown, suggesting that not only the composition of employment, but the nature of the shocks is important to understanding how the labor market adjusts.

This paper applies recent advances in the study of labor market dynamics to a representative developing country with a large informal or unregulated sector, Mexico. It studies quarterly gross flows of workers over a 15-year period that includes two recoveries and recessions, including the celebrated 1995 Tequila crisis. It finds, first, that the formal or modern salaried sector shows the same procyclical job finding rate and mildly countercyclical separation behavior identified in the recent U.S. literature, and relative wage rigidity, both consistent with Shimer (2005a) and Hall (2005). The unregulated informal sector, however, shows reasonable acyclicality in the job finding rate coupled with sharp countercyclical movements in the job separation rate, consistent with standard small firm dynamics and Davis and Haltiwanger (1992 and 1999). This interaction of regulatory coverage and firm sizes, and patterns of gross worker flows thus sheds suggestive light on the roots of countercyclical job finding behavior in the U.S. literature. Second, the patterns of worker transitions between formality and informality correspond to the job-to-job dynamics observed in the United States and not to the traditional idea of informality constituting the inferior sector of a segmented market. That said, the countercyclical job finding in the formal sector combined with the acyclical job finding in informality does lead to the latter absorbing relatively more labor during downturns. Third, aggregate employment dynamics vary across the Tequila crisis and the later 2001 slowdown, suggesting that not only the composition of employment, but the nature of the shocks is important to understanding how the labor market adjusts.

We combine information from several different studies and data sets to assemble a fuller, more accurate picture of job flows and worker flows in U.S. labor markets. Our picture characterizes the magnitudes of job and worker flows, the connections between them, their cyclical behavior, differences among identifiable groups of workers and employers, the spatial concentration of job flows, and other aspects of labor market dynamics. We also assess the relative strengths and weaknesses of the U.S. data sets that are currently available for measuring labor market flows, and we clarify the relationships among various measures of labor market flow activity that appear in the literature. Finally, we discuss prospects for using administrative records maintained by U.S. government agencies to develop new longitudinal data sets that would permit timely, detailed and comprehensive measures of gross job and worker flows

We build a three-state general equilibrium model of the aggregate labor market that features both standard labor supply forces and labor market frictions. Our model matches key features of the cyclical properties of employment, unemployment, and nonparticipation as well as those of gross worker flows across these three labor market states. Our key finding is that shocks to labor market frictions play a dominant role in accounting for labor market fluctuations. This is in contrast to the focus of the traditional RBC literature, which emphasized how employment fluctuations arise as a consequence of labor supply responses to price changes induced by TFP shocks.

Labor Markets and Business Cycles integrates search and matching theory with the neoclassical growth model to better understand labor market outcomes. Robert Shimer shows analytically and quantitatively that rigid wages are important for explaining the volatile behavior of the unemployment rate in business cycles. The book focuses on the labor wedge that arises when the marginal rate of substitution between consumption and leisure does not equal the marginal product of labor. According to competitive models of the labor market, the labor wedge should be constant and equal to the labor income tax rate. But in U.S. data, the wedge is strongly countercyclical, making it seem as if recessions are periods when workers are dissuaded from working and firms are dissuaded from hiring because of an increase in the labor income tax rate. When job searches are time consuming and wages are flexible, search frictions--the cost of a job search--act like labor adjustment costs, further exacerbating inconsistencies between the competitive model and data. The book shows that wage rigidities can reconcile the search model with the data, providing a quantitatively more accurate depiction of labor markets, consumption, and investment dynamics. Developing detailed search and matching models, Labor Markets and Business Cycles will be the main reference for those interested in the intersection of labor market dynamics and business cycle research.