Consumption Wealth Research Articles

Re‐Examining the Consumption–Wealth Relationship: The Role of Model Uncertainty

This paper discusses the consumption–wealth relationship. We use data on consumption, assets, and labor income and a vector error correction framework. This framework defines a set of models that differ in the number of co‐integrating vectors, the form of deterministic components and lag length. Further models can be defined through parametric restrictions and, in particular, interest centers on a weak exogeneity restriction that says that the co‐integrating residuals do not affect consumption and income directly. Key results in previous work relate to the roles of permanent and transitory shocks in driving wealth and how consumption responds to these shocks. We investigate the robustness of these results to model uncertainty and argue for the use of Bayesian model averaging. We find that there is a large degree of model uncertainty. Whether this uncertainty has important empirical implications depends on the researcher's attitude toward the theory used to motivate a co‐integrating relationship between consumption, assets and income. If we work with models consistent with this theory and impose the weak exogeneity restriction, we find precisely estimated results that show that permanent shocks have only a small role in driving assets and that the predominant transitory shocks have little effect on consumption. These findings are consistent with the previous literature. However, if we work with a broader set of models and let the data speak, we find that the exact magnitude of the role of permanent shocks is hard to estimate precisely. Thus, although some support exists for the view that their role is small, we cannot rule out the possibility that they have a substantive role to play.

Multiperiod Optimal Investment-Consumption Strategies with Mortality Risk and Environment Uncertainty

In this article we investigate three related investment-consumption problems for a risk-averse investor: (1) an investment-only problem that involves utility from only terminal wealth, (2) an investment-consumption problem that involves utility from only consumption, and (3) an extended investment-consumption problem that involves utility from both consumption and terminal wealth. Although these problems have been studied quite extensively in continuous-time frameworks, we focus on discrete time. Our contributions are (1) to model these investmentconsumption problems using a discrete model that incorporates the environment risk and mortality risk, in addition to the market risk that is typically considered, and (2) to derive explicit expressions of the optimal investment-consumption strategies to these modeled problems. Furthermore, economic implications of our results are presented. It is reassuring that many of our findings are consistent with the well-known results from the continuous-time models, even though our models have the additional features of modeling the environment uncertainty and the uncertain exit time.

Consumption, wealth and expected stock returns in Australia: some further results

This article re-examines the evidence that cay, the residual from a cointegrating regression of consumption on labour income and household wealth, is a useful predictor of excess stock returns in Australian data. In recursive samples beginning in 1976:q4 and ending from 1990:q1 to 2003:q1, cay is a strong predictor of excess returns. In samples that end thereafter, cay loses its predictive power for returns. This is due to a break-down in the cointegrating relation among consumption, labour income and household wealth following recent developments in the housing and stock markets.

Household Life-Cycle Effects on Consumer Wealth and Well-Being for the Recently Retired

The present research tests a series of predicted relationships regarding the e fects of household life-cycle variables, as well as other important consumer characteristics, on both wealth and perceived well-being among retired households. Toward that objective, separate samples of retired married households (n = 1,938) and retired single-person households (n = 855) from the Health and Retirement Study (HRS) of the University of Michigan were analyzed in an investigation of the e fects of household marital and parenthood characteristics on both accumulated wealth and perceived well-being. After controlling for education, race, gender, and health e fects, the results demonstrate significant life-cycle e fects of marital status and number of children on consumer wealth. In addition, wealth at retirement age is found to be a significant predictor of overall well-being. The implications of these findings, as well as a series of suggestions for future research regarding the study of important changes in life-cycle circumstances, are discussed.

Consumption, wealth and business cycles in Germany

This paper studies the long-run relationship between consumption, asset wealth and income—the consumption–wealth ratio—based on German data from 1980 to 2003. We find that departures from this long-run relationship mainly predict adjustments in income. The German consumption–wealth ratio also contains considerable forecasting power for a range of business cycle indicators, including the unemployment rate. This finding is in contrast to earlier studies for some of the Anglo-Saxon economies that have shown that the consumption–wealth ratio reverts to its long-run mean mainly through subsequent adjustments in asset prices. While the German consumption wealth ratio contains little information about future changes in German asset prices, we report that the U.S. consumption–wealth ratio has considerable forecasting power for the German stock market. One explanation of these findings is that in Germany—due to structural differences in the financial and pension systems—the share of publicly traded equity in aggregate household wealth is much smaller than in the Anglo-Saxon countries. We discuss the implications of our results for the measurement of a potential wealth effect on consumption.

Dynamic consumption and asset allocation with derivative securities

This paper provides a model in which a long-term investor chooses consumption and optimal dynamic asset allocation, including a riskless bond, risky stock, and derivatives on the stock, when there is predictable variation in return volatility. We maximize a more general recursive utility function defined over intermediate consumption rather than terminal wealth in order to reflect the realistic problem facing an investor who is saving for the future. The paper obtains a solution to this problem which is exact for investors with unit elasticity of intertemporal substitution of consumption, and approximate otherwise. The optimal log consumption–wealth ratio is a function of stochastic volatility, and the consumption–wealth ratio is an increasing function of volatility for investors whose elasticity of intertemporal substitution of consumption is smaller than one, while it is a decreasing function of volatility for investors whose elasticity of intertemporal substitution of consumption is larger than one. Derivative securities are a significant tool for expanding investors’ dimension of risk-and-return tradeoffs, being a vehicle for the additional risk factor of stochastic volatility in the stock market. Non-myopic investors can utilize derivative securities, which provide access to volatility risk, to capitalize upon the time-varying nature of their opportunity set.

Decomposing Consumer Wealth Effects: Evidence on the Role of Real Estate Assets Following the Wealth Cycle of 1990-2002

During the period from 1990 to 2002, U.S. households experienced a dramatic wealth cycle, induced by a 369 percent appreciation in the value of real per capita liquid stock-market assets, followed by a 55 percent decline. However, despite predictions at the time by some analysts relying on life-cycle models of consumption, consumer spending in real terms continued to rise throughout this period. Using data that include the period from 1990 to 2005, traditional approaches to estimating macroeconomic wealth effects on consumption confront two puzzles: (i) econometric evidence of a stable cointegrating relationship among consumption, income, and wealth is weak at best; and (ii) life-cycle models that rely on aggregate measures of wealth cannot explain why consumption did not collapse when the value of stock-market assets declined so dramatically. We address both puzzles by decomposing wealth according to the liquidity of household assets. In particular, we find that significant appreciation in the value of real estate assets that occurred after the peak of the wealth cycle helped to sustain consumer spending from 2000 to 2005.

Decomposing Consumer Wealth Effects: Evidence on the Role of Real Estate Assets Following the Wealth Cycle of 1990-2002

During the period from 1990 to 2002, U.S. households experienced a dramatic wealth cycle, induced by a 369-percent appreciation in the value of real per capita liquid stock-market assets, followed by a 55-percent decline. However, despite predictions at the time by some analysts relying on life-cycle models of consumption, consumer spending in real terms continued to rise throughout this period. Using data from 1990 to 2005, traditional approaches to estimating macroeconomic wealth effects on consumption confront two puzzles: (i) econometric evidence of a stable cointegrating relationship among consumption, income, and wealth is weak at best; and (ii) life-cycle models that rely on aggregate measures of wealth cannot explain why consumption did not collapse when the value of stock-market assets declined so dramatically. We address both puzzles by decomposing wealth according to the liquidity of household assets. In particular, we find that significant appreciation in the value of real estate assets that occurred after the peak of the wealth cycle helped to sustain consumer spending from 2001 to 2005.

Can fluctuations in the consumption-wealth ratio help to predict exchange rates?

It is accepted that standard macroeconomic variables are not capable of predicting ex ante the majority of short term changes in exchange rates. Lettau and Ludvigson (2001) find that fluctuations in the common long-term trend in consumption, asset wealth, and labour income (hereby, consumption-wealth ratio) is a strong predictor of the excess returns. This study examines the role of the consumption-wealth ratio in predicting the change in the nominal exchange rate for seven industrialized economies. Evidence is found that fluctuations in the consumption wealth ratio help to predict in-sample all currencies. Out-of-sample, the results suggest that the consumption wealth ratio may play a significant role forecasting the Canadian dollar.

Does Aggregate Relative Risk Aversion Change Countercyclically over Time? Evidence from the Stock Market

Using a semiparametric estimation technique, we show that the risk-return tradeoff and the Sharpe ratio of the stock market increases monotonically with the consumption wealth ratio (CAY) across time. While early studies have commonly interpreted such a finding as evidence of the countercyclical variation in aggregate relative risk aversion (RRA), we argue that it mainly reflects changes in investment opportunities for two reasons. First, we fail to reject the null hypothesis of constant RRA after controlling for CAY as a proxy for the hedge against changes in the investment opportunity set. Second, by contrast with habit formation models but consistent with ICAPM, we find that loadings on the conditional stock market variance scaled by CAY are negatively priced in the cross-sectional regressions. For illustration, we replicate the countercyclical stock market risk-return tradeoff using simulated data from Guo's (2004) limited stock market participation model, in which RRA is constant and CAY is a proxy for shareholders' liquidity conditions.

The existence, uniqueness, and optimality of the terminal wealth depletion time in life-cycle models of saving under uncertain lifetime and borrowing constraint

In life-cycle models of saving under uncertain lifetime and borrowing constraint, the consumer's wealth must be depleted before the maximum lifetime. This paper investigates the existence, uniqueness, and optimality of the terminal wealth depletion time. It is proved that the optimal terminal wealth depletion time, if such exists, must be unique. If the equation that determines the optimal terminal wealth depletion has multiple solutions, then the location of the optimal solution will depend on the configuration of the solutions. An optimality test is developed to verify whether a candidate solution for the terminal wealth depletion time is indeed optimal. The paper introduces a method new to economics, the Dubovitskii–Milyutin adjoint equation, to analyze the properties of the optimal control problem.

Idiosyncratic Volatility, Stock Market Volatility, and Expected Stock Returns

We find that the value-weighted idiosyncratic stock volatility and aggregate stock market volatility jointly exhibit strong predictive power for excess stock market returns. The stock market risk–return relation is found to be positive, as stipulated by the capital asset pricing model; however, idiosyncratic volatility is negatively related to future stock market returns. Also, idiosyncratic volatility appears to be a pervasive macrovariable, and its forecasting abilities are very similar to those of the consumption–wealth ratio proposed by Lettau and Ludvigson.

Emotional Impact Analysis in Financial Regulation: Going Beyond Cost-Benefit Analysis

This Article advocates that financial regulators analyze, measure, and take into account the emotional impacts of their policies and procedures. Examples of emotional impacts are investor confidence, process concerns, and overall market or social mood. Investor confidence or trust in securities markets, process concerns about how much securities regulators actually deliberate over proposed rules, and financial anxiety or investment stress affect and are affected by financial economic variables, such as consumer debt, consumer expenditures, consumer wealth, corporate investment, initial public offerings, and securities market demand, liquidity, prices, supply, and volume. Cost-benefit analysis does not quantitatively consider interdependencies between regulations' emotional impacts and their financial outcomes. Emotional impact analysis does. This Article addresses general conceptual and measurement issues about emotional impact analysis. Because financial regulations affect investors' confidence, process concerns, and social moods, this Article analyzes how financial regulators can quantitatively analyze emotional impacts of their regulations.

Interpreting the predictive power of the consumption–wealth ratio

Lettau and Ludvigson [Lettau, M., Ludvigson, S.C., 2001a. Consumption, aggregate wealth and expected stock returns. Journal of Finance 56, 815–849] find that the estimated consumption–wealth ratio ( cay ) is a strong predictor of U.S. stock returns, while Brennan and Xia [Brennan, M.J., Xia, Y., 2005. tay's as good as cay . Finance Research Letters 2, 1–14] argue that the predictive power of cay arises from a look-ahead bias. In a unified framework, we examine how the presence of deterministic time trends affects the estimation and forecasting power of cay . We show that ignoring the presence of a deterministic time trend in estimating the cointegrating relationship among consumption, asset wealth, and labor income leads to a biased estimate of the consumption–wealth ratio. In the presence of a deterministic time trend, cay is a combination of the highly persistent bias component and the unbiased cointegrating residual, and most of the predictive power of cay is attributable to the bias component, casting doubt on the robustness of the forecasting power of cay .

Empirical proxies for the consumption–wealth ratio

Using a log-linearized approximation to an aggregate budget constraint, it is possible to show that the ratio of consumption to total (human and non-human) wealth summarizes agents' expectations concerning both future labor income and future asset returns. In a series of recent papers, Lettau and Ludvigson construct an empirical analogue to the consumption–wealth ratio by approximating total wealth with a linear combination of labor income and observable non-human wealth. If valid, this framework suggests that consumption, assets, and labor income will be cointegrated. We demonstrate, however, that standard tests fail to reject the hypothesis of no cointegration once one employs measures of consumption, assets, and labor income that are jointly consistent with an underlying budget constraint. We also show that deviations of consumption, assets, and income from an estimated common trend are unable to predict future excess returns on stocks out of sample once theoretically consistent measures are used.

Preferences and the Dynamic Representative Consumer

This paper provides families of time-separable, twice continuously differentiable, and strictly concave utility functions of a group of consumers that are both sufficient and necessary in order to have linear aggregation in a single-commodity-type deterministic dynamic environment, in the presence of consumer wealth-, labor-productivity, and preference heterogeneity, for alternative settings where the rates of time preference can be the same or different across consumers. The employed concept of linear aggregation pertains the existence of a representative consumer with a time-separable utility function. It is proved that when the rates of time preference are choice-independent and heterogeneous across consumers, a representative consumer exists if, and only if, the momentary utility functions of all consumers are exponential. Results are also provided for, (i) common across consumers choice-independent rates of time preference, and, (ii) heterogeneous choice-dependent rates of time preference, and compared with previously identified sufficient conditions for aggregation in the existing literature.

Consumption, Wealth and Business Cycles: Why is Germany Different?

This paper studies the long-run relationship between consumption, asset wealth and income – the consumption-wealth ratio – in Germany, based on data from 1980 to 2003. Earlier papers for the Anglo-Saxon economies have documented that departures of these three variables from their common trend signal future changes in asset prices. We find that for Germany they predict changes in income – the consumption wealth ratio predicts business cycles, not stock market cycles. Asset price changes are found to have virtually no effect on German consumption, both in the short as well as in the long-run. Conversely, German asset prices are predictable from the U.S. consumption-wealth ratio. We offer an explanation of these findings that emphasizes structural differences between the bank-based German financial system and the rather market-based Anglo-American system: stock ownership by private households is much less widespread in Germany than in the Anglo-Saxon economies and the share of publicly traded equity in household wealth is much smaller in Germany than in the U.S., the UK or Australia.

Winning the Oil Endgame: Innovation for Profits, Jobs, and Security

This synthesis for American business and military leaders is peer reviewed and independent. It lays out a road map for getting the U.S. completely off its dependence on oil. The authors' strategy involves the integration of four technological methods to displace oil: (1) utilizing oil twice as efficiently as it is currently used, (2) substituting biofuels for oil, (3) saved natural gas, and (4) using hydrogen as an option. The complete application of today's most efficient technologies (in a doubled-gross domestic product (GDP) 2025 economy) would save half of the U.S. oil consumption that is projected and it would cost half its forecasted cost per barrel. In addition, the non-oil substitutes for the remaining energy consumption would cost less than oil. Zero values are assigned to these comparisons to avoid many of oil's externalized costs, such as pollution, depletion, the costs incurred by rivalry with developing countries, and the costs incurred by military insecurity. The path suggested for the transition after oil will increase consumer wealth and choice, and will be lead by for profit businesses. Novel public policies that are market oriented are proposed to speed up this transition. The authors note that an investment of $180 billion over the next decade will bring $130 billion in annual savings by 2025. It will also revitalize the truck, hydrocarbon, aviation and automotive industries; rebalance trade; create a million jobs in both rural and industrial areas; make the world more peaceful, fair and developed; and make the United States more prosperous, environmentally healthy, equitable and secure. In the discussion of how to get off oil, attention is paid in the paper to modes of transportation that use oil, including airplanes, ships, trains, automobiles, and buses.

A puzzle for adaptive theory

Over the life cycle aspirations for material goods grow commensurately with consumer wealth. But aspirations for marriage and the number and “quality” of children do not change much. The puzzle is why there is this difference between life domains in the extent to which aspirations adapt to actual circumstances. The findings come from a cohort analysis of 1978 and 1994 survey responses on the good life.

Tay's as good as cay

The empirical evidence that the consumption–wealth ratio, cay, has strong in-sample predictive power for future stock returns has been interpreted as evidence that consumers take account of future investment opportunities in planning their consumption expenditures. In this paper we show that the predictive power of cay arises mainly from a “look-ahead bias” introduced by estimating the parameters of the cointegrating regression between consumption, assets, and labor income in-sample. When a similar regression is run, replacing the log of consumption with an inanimate variable, calendar time, the resulting residual, which we label tay, is shown to be able to forecast stock returns as well as, or better than, cay. In addition, both cay and tay lose their out-of-sample forecasting power when they are re-estimated every period with only available data.