Taxation of capital income in overlapping generations economies

Whether capital income should be taxed in overlapping generations economies is vividly discussed. It is shown that intergenerational lump‐sum taxes cannot implement the Golden Rule allocation when agents have private information on their earnings potential. Hence, the seminal Atkinson–Stiglitz result that optimal income taxation pre‐empts any role for indirect taxation cannot be interpreted to imply that capital income taxation (affecting intertemporal relative prices) should not be taxed. Specifically, capital income should unambiguously be taxed in small open economies, and the optimal tax rate depends inversely on the elasticity of total savings to disposable income and the after‐tax rate of return.     

Increasing returns to savings and wealth inequality

In this paper I present an explanation to the fact that in the data wealth is substantially more concentrated than income. Starting from the observation that the composition of households' portfolios changes towards a larger share of high-yield assets as the level of net worth increases, I first use data on historical asset returns and portfolio composition by wealth level to construct an empirical return function. I then augment an Overlapping Generation version of the standard neoclassical growth model with idiosyncratic labor income risk and missing insurance markets to allow for returns on savings to be increasing in the level of accumulated assets. The quantitative properties of the model are examined and show that an empirically plausible difference between the return faced by poor and wealthy agents is able to generate a substantial increase in wealth inequality compared to the basic model, enough to match the Gini index and all but the top 1 percentile of the US distribution of wealth.     

THE WELFARE GAINS OF AGE‐RELATED OPTIMAL INCOME TAXATION

Using an overlapping generations model with skill uncertainty and private savings, we quantify the gains of age‐dependent labor income taxation. The total steady‐state welfare gain of switching from age‐independent to age‐dependent nonlinear taxation varies between 2.4% and 4% of GDP. Part of the gain descends from relaxing incentive–compatibility constraints and part is due to capital‐accumulation effects. The welfare gain is of about the same magnitude as that which can be achieved by moving from linear to nonlinear income taxation. Finally, the welfare loss from tax‐exempting interest income is negligible under an optimal age‐dependent labor income tax.     

Social Comparisons and Optimal Taxation in a Small Open Economy

In this paper, we analyze how international capital mobility affects the optimal labor and capital income tax policy in a small open economy when consumers care about relative consumption. The main results crucially depend on whether the government can tax returns on savings abroad. If the government can use flexible residence‐based capital income taxes, then the optimal policy rules from a closed economy largely carry over to the case of a small open economy. If it cannot, then capital income taxes become completely ineffective. The labor income taxes must then indirectly also reflect the corrective purpose that the absent capital income tax would have had.     

Optimal Social Insurance with Linear Income Taxation*

We study optimal social insurance aimed at insuring disability risk in the presence of linear income taxation. Optimal disability insurance benefits rise with previous earnings. Optimal insurance is incomplete even though disability risks are exogenous and verifiable so that moral hazard in disability insurance is absent. Imperfect insurance is optimal because it encourages workers to insure themselves against disability by working and saving more, thereby alleviating the distortionary impact of the redistributive income tax on labor supply and savings.     

Optimal climate and fiscal policy in an OLG economy

This paper develops a climate–economy model to study the joint design of optimal climate and fiscal policies in economies with overlapping generations (OLGs). I demonstrate how capital taxation, if optimal, drives a wedge between the market costs of carbon (the net present value of marginal damages using the market interest rate) and the Pigouvian tax (the net present value of marginal damages using the consumption discount rate of successive OLGs). In contrast to deterministic infinitely lived representative agent models, at the optimum, the capital income tax is positive, the carbon price equals the market costs of carbon but it falls short of the Pigouvian tax when (i) preferences are not separable over consumption and leisure; and (ii) labor income taxes cannot be age-dependent. I also show that restrictions on climate change policy provide a novel rationale for positive capital income taxes.     

Time-consistent taxation in a dynastic family model with human and physical capital and a balanced government budget

Abstract .  This paper analyzes optimal, time consistent taxation in a dynastic family model with human and physical capital and with a balanced government budget. When tax revenue is used for publicly provided consumption or lump-sum transfers, leisure would be higher than its social optimum. Pareto optimal taxation requires taxing capital income more heavily than labour income and subsidizing investment at the same rate of the tax. Also, it requires either subsidizing labour at the same rate as a consumption tax or subsidizing consumption at the same rate as a labour income tax, and hence it is not a practical guide to policy. Further, a consumption tax, or equivalently a uniform income tax with investment subsidies at the same rate, can be improved on by taxing capital income more heavily than labour income.     

Capital income taxation,tax criteria,and intergenerational welfare

In a two-period overlapping-generations model, residence criteria are shown to be optimal with lump-sum transfers to the younger generation in a dynamically efficient open economy even if all wage income, corresponding to rent income under exogenous labor supply, is not taxed away. When tax revenues are also distributed to the older generation — which indeed may be desirable for short-term intergenerational welfare distribution reasons — a weighted average rule is derived for optimal international taxation. The taxation of domestic savings income follows the inverse elasticity rule in respect to savings and, surprisingly, higher investment elasticity increases the tax level. Finally, for a small open economy and for large identical economies, tax competition with a mixed scheme of residence-based taxes and source-based subsidies yields the same tax policy as tax cooperation with no restrictions on the domestic and international capital income tax instruments.     

Optimal income taxation in models with endogenous fertility

This paper studies the efficient taxation of factor income in infinite-lived models with elastic fertility choices. Two models are considered, one with physical capital only, and one with physical and human capital. In the model with physical capital only, capital income should be subsidized, while labor income taxed. In the model with two types of capital, instead, Ramsey optimality prescribes that the tax on physical capital is zero (negative), if effective labor is constant (decreasing) returns to scale in human capital and market goods, while the tax on human capital is negative and the tax on effective labor positive. Our findings depart from those obtained in immortal models with an endogenous labor supply and constant population growth, because physical and human capital affect the demand for fertility.     

Optimal age‐dependent income taxation in a dynamic extensive model: The case for negative participation tax on young people

We consider optimal age‐dependent income taxation in a dynamic model where the labor‐leisure choice is the extensive margin, each household faces idiosyncratic shocks to labor productivity and a pecuniary cost to work, and there is no insurance market against the shocks. We show that the well‐known property of the optimal participation tax rate in the static model continues to hold in our dynamic economy, that is, the participation tax rates for some income groups with low consumption are likely negative. In dynamic models, the optimal participation tax rate depends on age and on labor income. Our numerical simulations suggest that a negative participation tax should be restricted to young households.     

Stochastic dominance and thick-tailed wealth distributions

Right-skewed and thick-tailed wealth distributions have been documented as an empirical regularity across space and time. A key mechanism for explaining these distributional features is proportional random growth. We investigate the comparative statics of a well-defined class of random growth models when allowing for stochastically ordered shifts in the wealth return process. An order-contingent monotone comparative statics property is identified, according to which pure increases in risk (e.g. higher volatility of capital returns) foster top wealth concentration whereas first-order stochastically dominated shifts in the return process (induced by e.g. proportional capital income taxation) rather lower inequality at the upper end of the distribution. Our analysis points to the potentially ambiguous effects on top wealth inequality of introducing or modifying capital income tax treatments in the presence of stochastic returns.     

Optimal Income Taxation with Endogenous Human Capital

This paper augments the theory of optimal linear income taxation by taking into account human capital accumulation as a dimension of labor supply. The distribution of earning potentials is endogenous because agents differ in the ability to learn. Taxation affects utilization rates of human capital through labor supply responses. The costs of education that are not deductible from the income tax distort the learning decision as well. We show theoretically that the trade‐off between efficiency and equity is worsened. Quantitative analysis shows that the distortionary costs of taxation increase substantially when human capital formation is endogenous.     

Redistributive taxation as social insurance

The modern literature on nonlinear optimal taxation treats differences in income as being due to unobserved differences in ability. A striking result of this assumption is that high income agents should face a zero marginal tax rate. In this paper I assume that differences in observed income are due to exogenous differences in luck. Hence the optimal redistributive tax involves trading off the benefits due to ‘social insurance’ with the costs due to reduced incentives. I derive the optimal forms for linear and nonlinear taxes, and compute some algebraic and numeric examples. Typically high income individuals will face quite high marginal tax rates.     

Optimal Capital Income Taxation with Means‐tested Benefits

This paper studies the interaction between capital income taxation and a means‐tested age pension. Our results document that the existence of a social insurance program financed from general revenue puts an upward pressure on the optimal tax rate. We also show that there is a negative relation between taper (benefit‐reduction) and optimal capital income tax rates. The potential welfare gain from optimizing capital taxation in the presence of a universal retirement transfer system is relatively higher. However, when the transfer is substantially means tested, the gain is lower, because the means test effectively operates as a tax on retirement capital.     

Is Altruism Important for Understanding the Long-Run Effects of Social Security?

This paper quantifies the effects of social security on capital accumulation and wealth distribution in a life-cycle framework with altruistic individuals. The main findings of this paper are that the current U.S. social security system has a significant impact on capital accumulation and wealth distribution. I find that social security crowds out 8% of the capital stock of an economy without social security. This effect is driven by the distortions of labor supply due to the taxation of labor income rather than by the intergenerational redistribution of income imposed by the social security system. In contrast to previous analysis, I found that social security does not affect the savings rate of the economy. Another interesting finding is that even though the current U.S. social security system is progressive in its benefits, it may lead to a more dispersed distribution of wealth. Journal of Economic Literature Classification Numbers: D31, D58, E2, E6, H55, J22, J26.     

Risky human capital and deferred capital income taxation

We study the structure of optimal wedges and capital taxes in a dynamic Mirrlees economy with endogenous distribution of skills. Human capital is a private, stochastic state variable that drives the skill process of each individual. Building on the findings of the labor literature, we construct a tractable life-cycle model of human capital evolution with risky investment and stochastic depreciation. In this setting, we demonstrate the optimality of (a) a human capital premium, i.e., an excess return on human capital relative to physical capital, (b) a large intertemporal wedge early in the life-cycle, and (c) a non-zero intratemporal wedge even at the top of the skill distribution at all dates except the last date in the life-cycle. The main implication for the structure of optimal linear capital taxes is the necessity of deferred taxation of physical capital. The average marginal tax rate on physical capital held in every period is zero in present value. However, expected capital tax payments do not equal zero in every period. Necessarily, agents face negative expected capital tax payments early in the life-cycle and positive expected capital tax payments late in the life-cycle.     

Optimal fiscal policy in the Uzawa-Lucas model with externalities

Summary. This paper devises a fiscal policy by means of which the first-best optimum equilibrium is attained as a market equilibrium in the Uzawa-Lucas model when average human capital has an external effect on productivity. The optimal policy requires the use of a subsidy to investment in human capital which can be financed by a tax on labor income. Lump-sum taxation is not required to balance the government budget either in the steady state or in the transitional phase. Physical capital income should not be taxed. Alternatively, the optimal growth path can be attained by means of a subsidy to human capital. Received: March 21, 2002; revised version: September 4, 2002 RID="*" ID="*" Financial support from the Spanish Ministry of Science and Technology through PNICDYIT grant SEC2002-03663 is gratefully acknowledged.     

Optimal human capital policies under the endogenous choice of educational types

This study examines optimal human capital policies under nonlinear labor and capital income taxes in the presence of consumption value of education in a two‐period setting. We show that when individuals can choose educational types differing by the relative importance of consumption value and production value, education subsidies for low‐type individuals should not equal an efficient level that offsets distortions induced by nonlinear taxes on labor and capital income. Our findings imply that education policy does not restore efficiency, or the Diamond–Mirrlees production efficiency theorem fails. Moreover, capital income taxation is optimal, which means that the Atkinson–Stiglitz theorem breaks down.     

Intergenerational Allocation of Government Expenditures: Externalities and Optimal Taxation

This paper studies optimal capital and labor income taxes when the benefits of public goods are age‐dependent. Provided the government can impose a consumption tax, it can attain the first‐best resource allocation. This involves the uniform taxation of the cohorts' labor income and a zero capital income tax. With no consumption tax and optimally chosen government spending, labor income should be taxed nonuniformly across cohorts and the capital income tax should be nonzero. Deviations of the public goods from their respective optima create distortions. These affect the labor supply decisions of both cohorts and capital accumulation, providing a further reason to tax (or subsidize) capital income.