Optimal Tax Design Research Articles

A Fair Day’s Pay for a Fair Day’s Work: Optimal Tax Design as Redistributional Arbitrage

A Fair Day’s Pay for a Fair Day’s Work: Optimal Tax Design as Redistributional Arbitrage

Optimal Tax Design: Choice of Tax Base and Rate Structure

Optimal Tax Design: Choice of Tax Base and Rate Structure

Investment Allocation with Capital Constraints. Comparison of Fiscal Regimes

The dramatic fall in oil prices after 2014 has led to more extensive capital rationing in international oil companies, and subsequent fierce competition between resource extraction countries to attract scarce investment. This situation is not adequately addressed by the large general literature on international taxation and multinational companies, since it fails to take account of capital rationing in its assumption that companies sanction all projects with a positive net present after-tax value. The paper examines the effect of tax design on international capital allocation when companies ration capital. We analyse capital allocation and government take for four equal oil projects in three different fiscal regimes: the U.S. GoM, UK upstream and Norway offshore. Implications for optimal tax design are discussed.

Optimal Taxation in a Federation and GST in India

Optimal tax models, starting from Ramsey (1927), are often studied using a single government. However, there are several countries which are federations and in that multiple levels of government have fiscal authority, which masks the heterogeneity across states. In this paper we study a federation with two states and a federal government. We first find that the optimal tax design indicates tax smoothing across the states and consumption smoothing across states and time. Moreover, optimal consumption is found to be independent of the tax rates. We also find that all governments cannot have zero borrowing simultaneously. Then we characterize two equilibria, one where both federal and state governments impose taxes and two, where only the federal government imposes tax. We find that in the first equilibrium, states potentially impose different tax rates, but consumption across states are the same. In an equilibrium with a single federal tax, consumption is smooth across time, but may not be equal across states. However, aggregate consumption in the economy is greater in the second equilibrium. India has adopted a nationwide GST system, moving away from multiple taxation. So, we then calibrate the model to Indian data and find the revenue neutral tax rates. We find that the highest revenue neutral tax rate is 20.1% and the median rate is 11.4%. Using the calibrated indirect tax rates in a regression analysis, we find that tax rates at the state level is negatively related to the growth rate of the state. So, after the implementation of GST in India, some states may see a higher level of consumption tax rate in the state and hence, a fall in growth rate.

Petroleum Tax Competition Subject to Capital Rationing

The recent dramatic fall in oil prices has led to extensive capital rationing in international oil companies, and subsequent fierce competition between resource extraction countries to attract scarce investment. This situation is not adequately addressed by the large literature on international taxation and multinational companies, since it fails to take account of capital rationing in its assumption that companies sanction all projects with a positive net present value. The paper examines the effect of tax design on international capital allocation when companies ration capital. We analyse capital allocation and government take for four equal oil projects in three different fiscal regimes: the US GoM, UK upstream and Norway offshore. Implications for optimal tax design are discussed.

Petroleum Tax Competition Subject to Capital Rationing

The recent dramatic fall in oil prices has led to extensive capital rationing in international oil companies, and subsequent fierce competition between resource extraction countries to attract scarce investment. This situation is not adequately addressed by the large literature on international taxation and multinational companies, since it fails to take account of capital rationing in its assumption that companies sanction all projects with a positive net present value. The paper examines the effect of tax design on international capital allocation when companies ration capital. We analyse capital allocation and government take for four equal oil projects in three different fiscal regimes: the US GoM, UK upstream and Norway offshore. Implications for optimal tax design are discussed.

When a Price is Enough: Implementation in Optimal Tax Design

This paper studies the design of tax systems that implement a planner's second-best allocation in a market economy. An example shows that the widely used Mirrleesian (1976) tax system cannot implement all incentive-compatible allocations. Hammond's (1979) principle of taxation proves that any incentive-compatible allocation can be implemented through at least one tax system. However, this tax system is often undesirable since it severely restricts the choice space of agents in the economy. In this paper we derive necessary and sufficient conditions to verify whether a given tax system can implement a given incentive-compatible allocation. We show that when an incentive-compatible allocation is on the Pareto frontier, and/or surjective onto the choice space, a tax system that equates the marginal tax rates to the optimal wedges can implement the second best, without restricting the choice space of the agents. It follows that the Mirrleesian tax system can successfully implement the second best in the identified classes. Since the second-best allocation of welfarist planners is always on the Pareto frontier, our results (ex post) validate most tax systems proposed in the literature. Outside of the identified classes, the planner may need to restrict the choice space of agents to implement its second best in the market. This sheds new light on rules, quotas and prohibitions used in real-world tax and benefit systems.

Optimal Income Taxation with Adverse Selection in the Labour Market

This article studies optimal linear and non-linear redistributive income taxation when there is adverse selection in the labour market. Unlike in standard taxation models, firms do not know workers' abilities, and competitively screen them through non-linear compensation contracts, unobservable to the government, in a Miyazaki–Wilson–Spence equilibrium. Adverse selection leads to different optimal tax formulas than in the standard Mirrlees (1971) model because of the use of work hours as a screening tool by firms, which for higher talent workers results in a “rat race”, and for lower talent workers in informational rents and cross-subsidies. The most surprising result is that, if the government has sufficiently strong redistributive goals, welfare is higher when there is adverse selection than when there is not. Policies that endogenously affect adverse selection are discussed. The model has practical implications for the interpretation, estimation, and use of taxable income elasticities, which are central to optimal tax design.

When a Price is Enough: Implementation in Optimal Tax Design

When a Price is Enough: Implementation in Optimal Tax Design

Optimal Income Taxation with Adverse Selection in the Labor Market

This paper studies optimal linear and nonlinear redistributive income taxation when there is adverse selection in the labor market. Unlike in standard taxation models, firms do not know workers’ abilities and competitively screen them through nonlinear compensation contracts. The equilibrium concept used is the Miyazaki-Wilson-Spence (MWS) one, adapted to a labor market with taxes. The government observes neither abilities nor the private market contracts and has to foresee the reaction of firms, in addition to workers. Adverse selection leads to different responses to taxes than in the standard Mirrlees (1971) model, because of the use of work hours as a screening tool by firms, which for higher talent workers results in a rat race. Accordingly, the new optimal income tax formulas include corrective terms for the rat race and redistributive terms take into account the informational rents and cross-subsidies received by lower productivity workers. The most surprising result is that, if the government has sufficiently strong redistributive goals, welfare is higher when there is adverse selection than when there is not. This result is due to the rat race in which high productivity workers are caught, which limits their flexibility to react adversely to distortive taxation. I draw the link to policy praxis by discussing various policies that a government can use to endogenously affect adverse selection. The model also has practical implications for the interpretation, estimation, and use of taxable income elasticities, which are central to optimal tax design.

Trends and Trade-Offs in Petroleum Tax Design

Topical issues in petroleum tax design are in this chapter discussed by means of a tax model for a net income tax system (Norway) and a representative PSA regime. We analyse the entire life cycle of a typical petroleum project, i.e., the exploration decision is included. Many petroleum tax systems are regressive, and thus not able to cope with high increases or decreases in the oil price. Accordingly, many countries are seeking to include progressive elements in their tax system. We discuss the trade-off between progressivity on the one hand and the optimal sharing of risk and investment between the oil companies and the host government on the other. Optimal risk sharing and optimal allocation of cash flow over the project lifetime between host government and international oil company, often call for the oil company to fund the initial investments. The high front end loading of costs and the high risk on part of the oil company, calls for it to keep a substantial part of the upside if the project is successful. This limits the degree of progressivity that is possible to implement. Thus, optimal tax design is contingent on the relative characteristics of the host government and the oil companies - who is better able to carry downside risk and who is the more impatient in terms of getting revenue. Also, the tax system must be curtailed to the attractivity of the petroleum projects available.

Taxes and Pensions

Pension benefit rules depend on individual history far more than taxes do, and age plays a much larger role in pension determination than in tax determination. Apart from some simulation studies, theoretical studies of optimal tax design typically contain neither a mandatory pension system nor the behavioral dimensions that lie behind justifications commonly offered for mandatory pensions. Conversely, optimizing models of pension design typically do not include annual taxation of labor and capital incomes. After spelling out this contrast and reviewing (and rejecting) zero taxation of capital income based on the Atkinson‐Stiglitz and Chamley‐Judd results, this article raises the issue of tax‐favored retirement savings, a topic where the two subjects come together.

Taxes and Pensions

Pension benefit rules depend on individual history far more than taxes do, and age plays a much larger role in pension determination than in tax determination. Apart from some simulation studies, theoretical studies of optimal tax design typically contain neither a mandatory pension system nor the behavioral dimensions that lie behind justifications commonly offered for mandatory pensions. Conversely, optimizing models of pension design typically do not include annual taxation of labor and capital incomes. After spelling out this contrast and reviewing (and rejecting) zero taxation of capital income based on the Atkinson-Stiglitz and Chamley-Judd results, this article raises the issue of tax-favored retirement savings, a topic where the two subjects come together.

Optimal Tax Design and Enforcement with an Informal Sector

An optimal commodity tax approach is taken to compare trade taxes and VATs when some commodities are produced informally. Trade taxes apply to all imports and exports, including intermediate goods, while the VAT applies only to sales by the formal sector and imports. The VAT achieves production efficiency within the formal sector, but, unlike trade taxes, cannot indirectly tax profits. Making the size of the informal sector endogenous in each regime is potentially decisive. The ability of the government to change the size of the informal sector through costly enforcement may also tip the balance in favor of the VAT. (JEL E26, H21, H25)

Taxes and Pensions

Pension benefit rules depend on individual history far more than taxes do, and age plays a much larger role in pension determination than in tax determination. Apart from some simulation studies, theoretical studies of optimal tax design typically contain neither a mandatory pension system nor the behavioral dimensions that lie behind justifications commonly offered for mandatory pensions. Conversely, optimizing models of pension design typically do not include annual taxation of labor and capital incomes. After spelling out this contrast and reviewing (and rejecting) zero taxation of capital income based on the Atkinson-Stiglitz and Chamley-Judd results, this article raises the issue of tax-favored retirement savings, a topic where the two subjects come together.

Trading Off Tax Distortion and Tax Evasion

Tax evasion is modeled as a risky activity and integrated into a standard problem of optimal tax design. The private cost of risk-taking is treated as a welfare loss. In general, there is a trade-off between reducing the costs of tax evasion and tax distortion, and the optimal trade-off can be characterized by an explicit formula. Depending on the penalty structure, the private cost of risk-taking may or may not be affected by the structure of taxation. Two cases are studied. If the penalty is proportional to the amount of income evaded as suggested by Allingham and Sandmo, it is efficient to supplement a broad-based wage tax by a tax on specific consumption. If the penalty is proportional to the amount of tax evaded as suggested byYitzhaki, one would not do so. For equal penalty values, the former is shown to yield higher efficiency.

Trading Off Tax Distortion and Tax Evasion

Tax evasion is modeled as a risky activity and integrated into a standard problem of optimal tax design. It is shown that there is a trade off between reducing tax evasion and reducing tax distortion. Thus it is efficient to supplement a broad-based wage tax by a tax on specific consumption if the former is evaded and the latter not. The optimal tax structure can be characterized by an explicit formula.

Uncertainty, Commitment, and Optimal Taxation

This paper examines the optimal tax design problem in the presence of wage uncertainty. The wage has a continuous distribution, individuals are ex ante identical, preferences are separable in labor supply and goods, public policy aims at providing the population with social insurance, and the only restriction on the tax instruments is that emanating from lack of public observability of realized wages and labor supplies. We show that optimal tax structures depend crucially on whether it is labor supply or goods that consumers have to commit to before the resolution of uncertainty. Specifically, we prove that, in the absence of commitment, the social insurance problem collapses to the traditional optimal tax problem. Second, if labor supply is precommitted, it would be possible to effect a first‐best outcome. Third, commitment to goods would make indirect taxation a useful instrument of tax policy even in the presence of a general income tax; it requires differential tax treatment of committed and noncommitted goods. Finally, if preferences are separable between the two types of goods, precommitted goods must be taxed at a uniform rate lower than that on the noncommitted goods.

Externalities and optimal taxation

This paper reexamines the optimal tax design problem (income and commodities) in the presence of externalities. The nature of the second–best, and the choice of the tax instruments, are motivated by the informational structure in the economy. The main results are: (i) environmental levies (linear or nonlinear) differ in formula from Pigouvian taxes by the expressions for the optimal tax on private goods; (ii) externalities do not affect commodity tax formulas (linear and nonlinear) for private goods; (iii) externalities do not affect the income tax structure if commodity taxes are nonlinear and affect it if commodity taxes are linear; and (iv) a general income tax plus strictly Pigouvian taxes are sufficient for efficient taxation if individuals of different types have identical marginal rates of substitution (at any given consumption bundle).

Tagging and Taxing: The Optimal Use of Categorical and Income Information in Designing Tax/Transfer Schemes

This paper explores aspects of the optimal design of tax/transfer schemes that involve elements of both ‘tagging’ (the use of categorical benefits) and ‘means‐testing’ (income‐relation of benefits). Simulations suggest a striking qualitative dissimilarity between the group‐specific schedules optimally imposed on poorer and richer groups: broadly speaking, the optimal marginal tax rate is decreasing in income among the latter but increasing among the former. This latter observation, potentially important for policy, runs counter to the conventional wisdom from previous simulations. The reconciliation, we argue, lies in the role played in optimal tax design by the revenue constraint.