The Greek economy experienced a boom until 2007, followed by a prolonged depression resulting in a 25 percent shortfall of GDP by 2016. Informed by a detailed analysis of macroeconomic patterns in Greece, we estimate a rich dynamic general equilibrium model to assess quantitatively the sources of the boom and bust. Lower external demand for traded goods and contractionary fiscal policies account for the largest fraction of the Greek depression. A decline in total factor productivity, due primarily to lower factor utilization, substantially amplifies the depression. Given the significant adjustment of prices and wages observed throughout the cycle, a nominal devaluation would only have short-lived stabilizing effects. By contrast, shifting the burden of adjustment away from taxes toward spending or away from capital taxes toward other taxes would generate longer-term production and consumption gains. Eliminating the rise in transfers to households during the boom would significantly reduce the burden of tax adjustment in the bust and the magnitude of the depression.

Most firms begin very small, and large firms are the result of typically decades of persistent growth. This growth can be understood as the result of some form of organization capital accumulation. In the US, the distribution of firm size k has a right tail only slightly thinner than 1/k. This is shown to imply that incumbent firms account for most aggregate organization capital accumulation. And it implies potentially extremely slow aggregate convergence rates. A benchmark model is proposed in which managers can use incumbent organization capital to create new organization capital. Workers are a specific factor for producing consumption, and they require managerial supervision. Through the lens of the model, the aftermath of the Great Recession of 2008 is unsurprising if the events of late 2008 and early 2009 are interpreted as a destruction of organization capital, or as a belief shock that made consumers want to reduce consumption and accumulate more wealth instead.

The U.S. Great Recession featured a large decline in output and labor, tighter financial conditions, and a large increase in firm growth dispersion. We build a model in which increased volatility at the firm level generates a downturn and worsened credit conditions. The key idea is that hiring inputs is risky because financial frictions limit firms' ability to insure against shocks. An increase in volatility induces firms to reduce their inputs to reduce such risk. Out model can generate most of the decline in output and labor in the Great Recession and the observed increase in firms' interest rate spreads.

The outreach of macroprudential policies is likely limited in practice by imperfect regulation enforcement, whether due to shadow banking, regulatory arbitrage, or other regulation circumvention schemes. We study how such concerns affect the design of optimal regulatory policy in a workhorse model in which pecuniary externalities call for macroprudential taxes on debt, but with the addition of a novel constraint that financial regulators lack the ability to enforce taxes on a subset of agents. While regulated agents reduce risk taking in response to debt taxes, unregulated agents react to the safer environment by taking on more risk. These leakages undermine the effectiveness of macroprudential taxes but do not necessarily call for weaker interventions. A quantitative analysis of the model suggests that aggregate welfare gains and reductions in the severity and frequency of financial crises remain, on average, largely unaffected by even significant leakages.

Modern business cycle theory focuses on the study of dynamic stochastic general equilibrium models that generate aggregate fluctuations similar to those experienced by actual economies. We discuss how this theory has evolved from its roots in the early real business cycle models of the late 1970s through the turmoil of the Great Recession four decades later. We document the strikingly different pattern of comovements of macro aggregates during the Great Recession compared to other postwar recessions, especially the 1982 recession. We then show how two versions of the latest generation of real business cycle models can account, respectively, for the aggregate and the cross-regional fluctuations observed in the Great Recession in the United States.

Most firms begin very small, and large firms are the result of typically decades of persistent growth. This growth can be understood as the result of some form of capital accumulation—-organization capital. In the US, the distribution of firm size k has a right tail only slightly thinner than 1/k. This means that most capital accumulation must be accounted for by incumbent fi…rms. This paper describes a range of circumstances in which this implies aggregate convergence rates that are only about half of what they are in the standard Cass-Koopmans economy. Through the lens of the models described in this paper, the aftermath of the Great Recession of 2008 is unsurprising if the events of late 2008 and early 2009 are interpreted as a destruction of organization capital.

This paper formalizes and quantifies the secular stagnation hypothesis, defined as a persistently low or negative natural rate of interest leading to a chronically binding zero lower bound (ZLB). Output-inflation dynamics and policy prescriptions are fundamentally different from those in the standard New Keynesian framework. Using a 56-period quantitative life cycle model, a standard calibration to US data delivers a natural rate ranging from -1.5% to -2%, implying an elevated risk of ZLB episodes for the foreseeable future. We decompose the contribution of demographic and technological factors to the decline in interest rates since 1970 and quantify changes required to restore higher rates.

Drawing from confidential firm-level data of US manufacturing firms, we provide new evidence on the cyclicality of small and large firms. We show that the cyclicality of sales and investment declines with firm size. The effect is primarily driven by differences between the top 0.5% of firms and the rest. Moreover, we show that, due to the skewness of sales and investment, the higher cyclicality of small firms has a negligible influence on the behavior of aggregates. We argue that the size asymmetry is unlikely to be driven by financial frictions given 1) the absence of statistically significant differences in the behavior of production inputs or debt in recessions, 2) the survival of the size effect after directly controlling for proxies of financial strength, and 3) the predictions of a simple financial frictions model, in which unconstrained (large) firms contract more in recessions than constrained (small) firms.

We develop an equilibrium model of firm dynamics with random search in the labor market where hiring firms exert recruiting effort by spending resources to fill vacancies faster. Consistent with microevidence, fast-growing firms invest more in recruiting activities and achieve higher job-filling rates. These hiring decisions of firms aggregate into an index of economy-wide recruiting intensity. We study how aggregate shocks transmit to recruiting intensity, and whether this channel can account for the dynamics of aggregate matching efficiency during the Great Recession. Productivity and financial shocks lead to sizable pro-cyclical fluctuations in matching efficiency through recruiting effort. Quantitatively, the main mechanism is that firms attain their employment targets by adjusting their recruiting effort in response to movements in labor market slackness.