A problem facing the United States and many other countries is how to finance retirement consumption as the number of their workers per retiree falls. The problem with a savings for retirement systems is that there is a shortage of good savings opportunities given the nature of most current tax systems and governments’ limited ability to honor the debt it issues. We find that eliminating capital income taxes will greatly increase saving opportunities and make a savings-for-retirement system feasible with only modest amount of government debt. The switch from a system close to the current U.S. retirement system, which relies heavily on taxing workers’ incomes and making lump-sum transfers to retirees, to one without income taxes will increase the welfare of all birth-year cohorts alive today and particularly the welfare of the yet unborn cohorts. The equilibrium paths for the current and alternative policies are computed.

The neoclassical growth model is extended to include costly intermediated borrowing and lending between households. This is an important extension as substantial resources are used in intermediating the large amount of borrowing and lending between households. In 2007, in the United States, the amount intermediated was 1.7 times GNP, and the resources used in this intermediation amounted to at least 3.4 percent of GNP. The theory implies that financial intermediation services are an intermediate good and that the spread between borrowing and lending rates measures the efficiency of the financial sector.

There is a large amount of intermediated borrowing and lending between households. Some of it is intergenerational, but most is between older households. The average difference in borrowing and lending rates is over 2 percent. In this paper, we develop a model economy that displays these facts and matches not only the returns on assets but also their quantities. The heterogeneity giving rise to borrowing and lending and differences in equity holdings depends on differences in the strength of the bequest motive. In equilibrium, the lenders are annuity holders and the borrowers are those who have equity holdings, who live off its income when retired, and who leave a bequest. The borrowing rate and return on equity are the same in the absence of aggregate uncertainty. The divergence between borrowing and lending rates can thus give rise to an equity premium, even in a world without aggregate uncertainty.

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.

We build a variation of the neoclassical growth model in which both wealth shocks (in the sense of wealth destruction) and financial shocks to households generate recessions. The model features three mild departures from the standard model: (1) adjustment costs make it difficult to expand the tradable goods sector by reallocating factors of production from nontradables to tradables; (2) there is a mild form of labor market frictions (Nash bargaining wage setting with Mortensen-Pissarides labor markets); (3) goods markets for nontradables require active search from households wherein increases in consumption expenditures increase measured productivity. These departures provide a novel quantitative theory to explain recessions like those in southern Europe without relying on technology shocks.

We build a variation of the neoclassical growth model in which financial shocks to households or wealth shocks (in the sense of wealth destruction) generate recessions. Two standard ingredients that are necessary are (1) the existence of adjustment costs that make the expansion of the tradable goods sector difficult and (2) the existence of some frictions in the labor market that prevent enormous reductions in real wages (Nash bargaining in Mortensen-Pissarides labor markets is enough). We pose a new ingredient that greatly magnifies the recession: a reduction in consumption expenditures reduces measured productivity, while technology is unchanged due to reduced utilization of production capacity. Our model provides a novel, quantitative theory of the current recessions in southern Europe.

Macroeconomics is evolving from the study of aggregate dynamics to the study of the dynamics of the entire equilibrium distribution of allocations across individual economic actors. This article reviews the quantitative macroeconomic literature that focuses on household heterogeneity, with a special emphasis on the “standard” incomplete markets model. We organize the vast literature according to three themes that are central to understanding how inequality matters for macroeconomics. First, what are the most important sources of individual risk and cross-sectional heterogeneity? Second, what are individuals’ key channels of insurance? Third, how does idiosyncratic risk interact with aggregate risk?

This paper studies lifetime aggregate labor supply with endogenous workweek length. Such a theory is needed to evaluate various government policies. A key feature of our model is a nonlinear mapping from hours worked to labor services. This gives rise to an endogenous workweek that can differ across occupations. The theory determines what fraction of the lifetime an individual works, not when. We find that constraints on workweek length have different consequences for total hours than total labor services. Also, we find that policies designed to increase the length of the working life may not increase aggregate lifetime labor supply.

Robert Solow has criticized our 2006 Journal of Economic Perspectives essay describing “Modern Macroeconomics in Practice.” Solow eloquently voices the commonly heard complaint that too much macroeconomic work today starts with a model with a single type of agent. We argue that modern macroeconomics may not end too far from where Solow prefers. He is also critical of how modern macroeconomists use data to construct models. Specifically, he seems to think that calibration is the only way that our models encounter data. To the contrary, we argue that modern macroeconomics uses a wide variety of empirical methods and that this big-tent approach has served macroeconomics well. Solow also questions our claim that modern macroeconomics is firmly grounded in economic theory. We disagree and explain why.