节税收益、破产成本与最优资本结构

本文在正确定义债务的节税收益和破产成本的基础上,运用实物期权定义并定量描述了破产成本,进而建立了确定最优资本结构的ZZ杠杆模型。将自变量的典型值代入模型得出的最优债务比率与以往的实际调查数据非常接近,从而使一些长期难以解释的"资本结构之谜",例如"财务保守行为"等得到了一个合理的解释。     

On the Interaction of Real and Financial Decisions of the Firm Under Uncertainty

This study analyzes the interaction between the optimal level of investment and debt financing. For this purpose, a model is structured in which a firm, facing an uncertain price, has to decide on its optimal level of investment and debt. The amount of investment sets a limit on output whose optimal level is determined after price is realized. The debt involved is risky (there exists a possibility of bankruptcy). The analysis proves that investment and its optimal financing have to be simultaneously determined and that a negative relationship exists between operating and financial leverage. We also demonstrate that as the tax rate increases, optimal capacity decreases and optimal leverage increases. An analysis of the impact of changes in the expected price shows that under some conditions, an increase in expected price would lead to an increase in optimal investment (firm size) and a decrease in optimal debt.     

A Cost-Benefit Analysis of the Thailand Taxpayer Survey

We investigate whether more resources should be devoted to a Thai tax enforcement program which is aimed at bringing small businesses into the tax system. We show that the appropriate criteria for determining whether more resources should be devoted to tax enforcement is whether the Atkinson–Stern condition for the optimal provision of a publicly-provided good is satisfied, or equivalently, whether the marginal cost of finds obtained through additional tax enforcement, SMCF_p, is less than the marginal cost of funds obtained through raising tax rates, SMCF_t. In our base case scenario, the SMCF_p is 11.60 which exceeds our estimate of the SMCF_t for an across-the-board increase in income tax rates on wage earners. The use of pro-poor distributional weights makes expanding the survey less attractive if the alternative way of obtaining additional tax revenue is an across-the-board income tax rate increase, while aversion to tax evasion makes it more attractive.     

When are preferred shares preferred? Theory and empirical evidence

This paper demonstrates that preferred stock may arise as an optimal security in a tax-induced equilibrium. This result is driven by graduated tax schedules and by uncertainty. In a more general sense, our results can be interpreted as a template for including any security with a different tax treatment in a firm's capital structure. The first part of the paper demonstrates that the Miller equilibrium framework can accommodate more than two securities if different investor classes are taxed differently on each security and the tax schedule for each investor group is upward sloping. We then simplify the tax schedule, but introduce uncertainty, which implies the possibility of bankruptcy and the possible loss of tax shelters. The interaction of tax rates and seniority now affects the contribution of each security to after-tax firm value, as in some states the firm may not be able to pay either interest (or dividends) or even principal to its various claimholders. It is shown why and how these features, i.e. the various tax rates and seniority, determine the financing equilibrium, which is obtained by equating the expected marginal tax benefit of all securities. We demonstrate that non-profitable firms will tend to issue preferred shares whereas profitable firms will not find preferred stock advantageous in our framework. Comparative statics with respect to various tax rates are derived as well. These predictions are tested using a large sample of firms for the last 25 years. The empirical testing broadly confirms the theoretical predictions.     

Human capital and optimal positive taxation of capital income

This paper analyzes optimal linear and non-linear taxes on capital and labor incomes in a life-cycle model of human capital investment, financial savings, and labor supply with heterogenous individuals. A dual income tax with a positive marginal tax rate on not only labor income but also capital income is optimal. The positive tax on capital income serves to alleviate the distortions of the labor tax on human capital accumulation. The optimal marginal tax rate on capital income is lower than that on labor income if savings are elastic compared to investment in human capital, substitution between verifiable and non-verifiable inputs in human capital formation is difficult, and most investments in human capital are verifiable so that education subsidies can directly reduce the tax wedge on learning. Numerical calculations suggest that the optimal marginal tax rate on capital income is substantial.     

THE DEBT MATURITY CHOICE: AN EMPIRICAL INVESTIGATION

In this paper I develop and test three nonmutually exclusive hypotheses about the determinants of corporations' debt maturity choices using a sample of corporate bonds issued between 1982 and 1986. The empirical evidence strongly supports the hypothesis that firms use bond maturity to facilitate monitoring by outsiders (the monitoring hypothesis) and weakly supports the hypothesis that firms with high-quality projects use bond maturity to signal project quality (the signaling hypothesis). The evidence does not support the hypothesis that firms use bond maturity to achieve an optimal trade-off between interest tax shields and bankruptcy costs (the tax/bankruptcy cost hypothesis).     

Human Capital,Bankruptcy, and Capital Structure

We derive the optimal labor contract for a levered firm in an economy with perfectly competitive capital and labor markets. Employees become entrenched under this contract and so face large human costs of bankruptcy. The firm's optimal capital structure therefore depends on the trade‐off between these human costs and the tax benefits of debt. Optimal debt levels consistent with those observed in practice emerge without relying on frictions such as moral hazard or asymmetric information. Consistent with empirical evidence, persistent idiosyncratic differences in leverage across firms also result. In addition, wages should have explanatory power for firm leverage.     

Investment timing and optimal capital structure under liquidity risk

Deterioration in debt market liquidity reduces debt values and affects firms' decisions. Considering such risk, we develop an investment timing model and obtain analytic solutions. We carry out a comprehensive analysis in optimal financing, default, and investment strategies, and stockholder–bondholder conflicts. Our model explains stylized facts and replicates empirical findings in credit spreads. We obtain six new insights for decision makers. We propose a ‘new trade-off theory’ for optimal capital structure, a new tax effect, and new explanations of ‘debt conservatism puzzle’ and ‘zero-leverage puzzle’. Failure in recognizing liquidity risk results in substantially over-leveraging, early bankruptcy or investment, overpriced options, and undervalued coupons and credit spreads. In addition, agency costs are surprisingly small for a high liquidity risk or a low project risk. Interestingly, the risk shifting incentive and debt overhang problem decrease with liquidity risk under moderate tax rates while they increase under high tax rates.     

On the design of an optimal non-linear tax/pension system with habit formation

We study the optimal tax/pension design in a two-period model where individuals differ in both productivity and discount rates or projection bias and where their utility of the retirement period consumption is not independent of the earlier standard of living. We consider both welfarist and paternalistic social objectives. The paternalistic government attempts to correct the projection bias by using a higher discount factor. We derive general mathematical expressions that characterize optimal tax/pension design (marginal tax/subsidy rates). They suggest that the pattern of marginal labor income taxes depends on habit formation. Negative marginal labor income tax rates are possible. To gain a better understanding, we examine numerically the properties of an optimal lifetime redistribution policy with habit formation. We find support for non-linear tax/pension program in which some types of individuals are taxed while some are subsidized. The effect of changes in the degree of habit formation is explored in the numerical simulations as well as the implications of different degrees of correlation between skill and projection bias.     

The marginal cost of public funds is one at the optimal tax system

This paper develops a Mirrlees framework with skill and preference heterogeneity to analyze optimal linear and nonlinear redistributive taxes, optimal provision of public goods, and the marginal cost of public funds (MCF). It is shown that the MCF equals one at the optimal tax system, for both lump-sum and distortionary taxes, for linear and nonlinear taxes, and for both income and consumption taxes. By allowing for redistributional concerns, the marginal excess burden of distortionary taxes is shown to be equal to the marginal distributional gain at the optimal tax system. Consequently, the modified Samuelson rule should not be corrected for the marginal cost of public funds. Outside the optimum, the marginal cost of public funds for distortionary taxes can be either smaller or larger than one. The findings of this paper have potentially important implications for applied tax policy and social cost–benefit analysis.     

What determines corporate pension fund risk-taking strategy?

Corporate sponsors of defined benefit pension plans generally assume low investment risk when they have low funding ratios and high default risk, consistent with the risk management hypothesis. However, for financially distressed sponsors and sponsors that freeze, terminate, or convert defined benefit to defined contribution plans, the risk-shifting incentive (moral hazard) dominates. Pension fund risk-taking is also affected by labor unionization and sponsor incentives to maximize tax benefits, restore financial slack, and justify the accounting choices of pension assumptions. Sponsors shift toward an aggressive risk strategy when their pension plans emerge from underfunding, bankruptcy risk is reduced, or marginal tax rate decreases. Overall, we show that corporate sponsors adopt a dynamic risk-taking strategy in their pension fund investments.     

Financial leverage and corporate taxation: evidence from German corporate tax return data

To estimate the impact of profit taxation on the financial leverage of corporations, this study uses a pseudopanel constructed from comprehensive corporate tax return microdata for the period 1998–2001, which saw the introduction of major corporate tax reform in Germany. Financial leverage refers to the ratio of long-term debt to total capital. The endogeneity of the firm-specific marginal after-financing corporate income tax rate is controlled for by an instrumental variable approach. The instrument for the observed marginal tax rate is the counterfactual tax rate that a corporation would have faced in a particular period had there been no endogenous change, triggered by the tax reform, of its financial leverage and tax base. This counterfactual tax rate is derived from a detailed microsimulation model of the corporate sector, based on tax return microdata. The marginal tax rate has a statistically significant and relatively large positive effect on corporate leverage; for firms reporting positive profits, an increase of the marginal tax rate of 1 % would increase the financial leverage by approximately 0.7 %, on average. The debt ratio is less responsive to tax incentives for small corporations and firms facing high economic risks.     

HOW FIRM CHARACTERISTICS AFFECT CAPITAL STRUCTURE: AN INTERNATIONAL COMPARISON

In this empirical study I examine the factors correlated with capital structure in France, Germany, Japan, the United Kingdom, and the United States. Although mean leverage and many firm factors appear to be similar across countries, some significant differences remain. Specifically, differences appear in the correlation between long-term debt/asset ratios and the firms' riskiness, profitability, size, and growth. These correlations may be explained by differences in tax policies and agency problems, including differences in bankruptcy costs, information asymmetries, and shareholder/creditor conflicts. The findings of this study suggest links between varying choices in capital structure across countries and legal and institutional differences.     

On the Relevance of Debt Maturity Structure

In this paper, we present a tax-induced framework to analyze debt maturity problems. We show that under some modifications of the existing U.S. tax code, debt maturity is irrelevant even in the presence of taxes and bankruptcy costs that yield an optimal capital structure. If this restrictive structure is relaxed, and assuming the Miller [15] equilibrium does not prevail, tax reasons would usually imply the existence of an optimal debt maturity structure. If there exists a gain from leverage, then an increasing term structure of interest rates, adjusted for default risk, results in long-term debt being optimal. A decreasing term structure, under similar circumstances, renders short-term debt optimal. In the absence of agency costs, a Miller [15]-type result emerges at equilibrium and irrelevance prevails. We also argue that agency costs could again reverse the irrelevance and imply a firm-specific optimal debt maturity structure.     

The effects of population aging on optimal redistributive taxes in an overlapping generations model

The impact of population aging on the steady-state solution to an Ordover and Phelps (J. Public Econ. 12:1?C26, 1979) overlapping generations optimal nonlinear income tax problem with two types of worker and quasilinear-in-leisure preferences is investigated. A decrease in the rate of population growth, which leads to an aging population, increases the relative price of consumption per person in retirement, which tends to decrease optimal consumption for retirees of both skill types. Nevertheless, it is also shown that the optimal marginal income tax rates are independent of the rate of population growth. In addition, the steady-state interest rate unambiguously declines when the rate of population growth declines. Resulting adjustments in production plans have an ambiguous effect on the aggregate wage rate. This article identifies factors contributing to an increase in the aggregate wage when the population ages, namely normality of consumption in retirement, complementarity between capital and labor in production, and a large capital deepening effect relative to the increase in dependency owing to demographic change. Depending on the sign of this wage effect, ambiguities may arise in the direction of change in the optimal steady-state consumption and production plans. However, when the dependency effect is sufficiently strong, it is possible to sign the direction of change in all production and consumption plans. Moreover, regardless of the direction of change in optimal consumption plans, the absolute value of the changes in consumption plans are smaller for low-skilled workers than for high-skilled when utility is time-separable and preferences exhibit decreasing absolute risk aversion. Adopting, instead, a quasilinear-in-consumption specification of preferences sharpens the comparative statics of consumption allocations, but introduces ambiguity into the effect of the rate of population growth on the optimal marginal income tax rate.     

Dynamic optimal capital structure with regime switching

We investigate the optimal capital structure of a corporate when the dynamics of the assets (both growth rate and volatility) change following different states of the economy. Two structural models are examined in the paper. The first considers the case when the firm is not facing tax benefit and bankruptcy costs with a regime switching dynamics. This model extends the Black and Cox (J Financ 31:351–367, 1976) model to allow for regime switching risk. The second model incorporates both tax benefit and bankruptcy costs with a regime switching dynamics. This is is more realistic, and is an extension of the Leland (J Financ 49(4):1213–1252, 1994) model with regime switching risk. We obtain closed-form analytic solutions for the optimal capital structure and default barrier for both models.     

DESIGNING CAPITAL STRUCTURE TO CREATE SHAREHOLDER VALUE

In the past decade, many U.S. companies have launched aggressive share repurchase programs with the expectation that value can be created by returning excess capital to shareholders and moving the firm closer to its optimal capital structure. But how much capital does a company really need to support its business activities? This article presents an economic framework or “model” that can be used to simulate the effect of various capital structure choices on shareholder value. The fundamental insight underlying the model is that judicious use of debt can add value by reducing corporate taxes and strengthening management incentives to increase efficiency, but that too much debt can result in a loss of business and perhaps a costly reorganization. Indeed, one of the key findings of the authors' recent research is that companies with highly leveraged balance sheets suffer disproportionately large losses in market share and value during industry downturns. As illustrated in a case study of a hypothetical general merchandiser, the model makes it possible to identify an optimal debt-equity ratio (and percentage of fixed- versus floating-rate debt)—one that balances the value of the tax shield from debt against the increased risk of financial distress.     

Optimal Debt and Profitability in the Trade‐Off Theory

I develop a dynamic model of leverage with tax deductible interest and an endogenous cost of default. The interest rate includes a premium to compensate lenders for expected losses in default. A borrowing constraint is generated by lenders' unwillingness to lend an amount that would trigger immediate default. When the borrowing constraint is not binding, the trade‐off theory of debt holds: optimal debt equates the marginal interest tax shield and the marginal expected cost of default. Contrary to conventional interpretation, but consistent with empirical findings, increases in current or future profitability reduce the optimal leverage ratio when the trade‐off theory holds.     

Optimal redistributive tax and education policies in general equilibrium

This paper studies optimal linear and non-linear income taxes and education subsidies in two-type models with endogenous human capital formation, endogenous labor supply, and endogenous wage rates. Assuming constant human capital elasticities, human capital investment should be efficient under optimal linear policies, whether general equilibrium effects are present or not. Hence, education subsidies should not be used for distributional reasons. Due to general equilibrium effects, optimal linear income taxes may even become negative. Optimal non-linear policies exploit general equilibrium effects for redistribution. The high-skilled type optimally has a negative marginal income tax rate and a positive marginal education subsidy. The low-skilled type optimally faces a positive marginal income tax rate and a marginal tax on education. Simulations demonstrate that general equilibrium effects have only a modest effect on optimal non-linear policies.     

THE CAPITAL STRUCTURE PUZZLE: ANOTHER LOOK AT THE EVIDENCE

Since the formulation of the M & M irrelevance propositions 40 years ago, financial economists have been debating whether there is such a thing as optimal capital structure—a proportion of debt to equity that maximizes current firm value. Some finance scholars have followed M & M by arguing that both capital structure and dividend policy are largely “irrelevant” in the sense that they have no significant, predictable effects on corporate market values. Another school of thought holds that corporate financing choices reflect an attempt by corporate managers to balance the tax shields and disciplinary benefits of greater debt against the increased probability and costs of financial distress. Yet another theory says that companies do not have capital structure targets, but instead follow a financial pecking order in which retained earnings are preferred to outside financing, and debt is preferred to equity when outside funding is required. In reviewing the evidence that has accumulated since M & M, the authors argue that taxes, bankruptcy (and other “contracting”) costs, and information costs (the main factor in the pecking order theory) all appear to play an important role in corporate financing decisions. While much if not most of the evidence is consistent with the argument that companies set target leverage ratios, there is also considerable support for the pecking order theory's contention that firms are willing to deviate widely from their targets for long periods of time. According to the authors, the key to reconciling the different theories—and thus to solving the capital structure puzzle—lies in achieving a better understanding of the relation between corporate financing stocks (leverage ratios) and flows (specific choices between debt and equity). Even if companies have target leverage ratios, there will be an optimal deviation from those targets—one that will depend on the transactions and information costs associated with adjusting back to the target relative to the costs of deviating from the target. As the authors argue in closing, a complete theory of capital structure must take account of these adjustment costs and how they affect expected deviations from the target.