The paper studies how high leverage and crises can arise as a result of changes in the income distribution. Empirically, the periods 1920-1929 and 1983-2008 both exhibited a large increase in the income share of the rich, a large increase in leverage for the remainder, and an eventual financial and real crisis. The paper presents a theoretical model where these features arise endogenously as a result of a shift in bargaining powers over incomes. A financial crisis can reduce leverage if it is very large and not accompanied by a real contraction. But restoration of the lower income group's bargaining power is more effective.

This paper first documents the evolution of the cross-sectional income and consumption distribution in the US in the past 25 years. Using data from the Consumer Expenditure Survey we find that a rising income inequality has not been accompanied by a corresponding rise in consumption inequality. Over the period from 1972 to 1998 the standard deviation of the log of after-tax labor income has increased by 20% while the standard deviation of log consumption has increased less than 2%. Furthermore income inequality has increased both between and within education groups while consumption inequality has increased between education groups but mildly declined within groups. We then argue that these empirical findings are consistent with the hypothesis that an increase in income volatility has been an important cause of the increase in income inequality, but at the same time has lead to an endogenous development of credit markets, allowing households to better smooth their consumption against idiosyncratic income fluctuations. We develop a consumption model in which the sharing of income risk is limited by imperfect enforcement of credit contracts and in which the development of financial markets depends on the volatility of the individual income process. This model is shown to be quantitatively consistent with the joint evolution of income and consumption inequality in US, while other commonly used consumption models are not.

Studies the trend in household income uncertainty using a novel approach that measures income uncertainty as the variance of forecast errors at each future horizon separately without imposing parametric restrictions on the underlying income shocks. Household income uncertainty has risen significantly and persistently since the early 1970s. Their measure of near-future uncertainty in total family non-capital income rose 40% between 1971 and 2002. This rising uncertainty is likely due to the increase in variances of both persistent and transitory income shocks. The increase was most pronounced among single-earner households and high-income households. Charts and tables. This is a print on demand report.

Consumption decisions are crucial determinants of business cycles and growth. Knowledge of how consumers respond to the economic environment and how they react to the risks that they encounter during the life-cycle is therefore important for evaluating stabilization policies and the effectiveness of fiscal packages implemented in response to economic downturns or financial crises. In The Economics of Consumption, Tullio Jappelli and Luigi Pistaferri provide a comprehensive examination of the most important developments in the field of consumption decisions and evaluate economic models against empirical evidence. The first part of the book provides the basic ingredients of economic models of consumption decisions. The central part reviews the empirical literature on the effect of income and wealth changes on consumption and on the relevance of precautionary saving and credit market imperfections. The last chapters extend the basic framework to such important areas as bequests, leisure, lifetime uncertainty, and financial sophistication. Jappelli and Pistaferri shed light on important issues, including how consumption responds to changes in economic resources, how economic circumstances and consumers' characteristics influence behavior, and whether consumption inequality depends on income shocks and their persistence.

"Using data from the Consumer Expenditure Survey, we first document that the recent increase in income inequality in the United States has not been accompanied by a corresponding rise in consumption inequality. Much of this divergence is due to different trends in within-group inequality, which has increased significantly for income but little for consumption. We then develop a simple framework that allows us to analytically characterize how within-group income inequality affects consumption inequality in a world in which agents can trade a full set of contingent consumption claims, subject to endogenous constraints emanating from the limited enforcement of intertemporal contracts (as in Kehoe and Levine, 1993). Finally, we quantitatively evaluate, in the context of a calibrated general equilibrium production economy, whether this setup, or alternatively a standard incomplete markets model (as in Aiyagari, 1994), can account for the documented stylized consumption inequality facts from the U.S.data"--Federal Reserve Bank of Minneapolis web site.