Wage inequality has been significantly higher in the U.S. than in continental European countries since the 1970s. This report studies the role of labor income tax policies (LITP) for understanding these facts. Countries with more progressive LITP have significantly lower before-tax wage inequality at different points in time. Progressivity is also negatively correlated with the rise in wage inequality during this period. Wage inequality arises from differences across individuals in their ability to learn new skills as well as from idiosyncratic shocks. Progressive taxation compresses the (after-tax) wage structure, thereby distorting the incentives to accumulate human capital, in turn reducing the cross-sectional dispersion of (before-tax) wages. Illustrations. This is a print-on-demand publication; it is not an original.

What are the effects of taxation on individual/entrepreneurs’ risk-taking behavior? This paper re-examines this old question in a continuous time life-cycle model. We demonstrate that the stream of uncertain income from human capital has systematic effects on demand for the risky physical capital asset. If labor supply is inelastic and real wages are known with certainty, then a labor income tax will reduce holdings of the risky physical asset. However, if there are random fluctuations in labor income, then the effect depends on the nature of interaction between wage risk and investment income risk. A labor income tax may actually raise demand for the risky capital asset if human capital risk and physical capital risk are positively correlated. The idiosyncratic risk and nontradability of human capital also have implications for optimal taxation. When the insurance and disincentive effects are jointly taken into account, a Pareto efficient tax structure implies a strictly positive tax rate.

This article examines how to treat human capital -- perhaps the vast majority of the capital stock -- under an ideal, Haig-Simons income tax. Innate ability, investments in human capital, and uncertainty in future earnings are considered. It is demonstrated that conventional income tax treatment and proposed modifications are closer to implementing a consumption tax than an income tax. Approximating ideal income tax treatment may be feasible, but assessing its desirability would require further inquiry.

This paper examines the effects of taxation of human capital, physical capital and foreign assets in a multi-sector model of endogenous growth. It is shown that in general the growth rate is reduced by taxes on capital and labor (human capital) income. When the government faces no borrowing constraints and is able to commit to a given set of present and future taxes, it is shown that the optimal tax plan involves high taxation of both capital and labor in the short run. This allows the government to accumulate sufficient assets to finance spending without any recourse to distortionary taxation in the long run. When restrictions to government borrowing and lending are imposed, the model implies that human and physical capital should be taxed similarly.

Wage inequality has been significantly higher in the United States than in continental European countries (CEU) since the 1970s. Moreover, this inequality gap has further widened during this period as the US has experienced a large increase in wage inequality, whereas the CEU has seen only modest changes. This paper studies the role of labor income tax policies for understanding these facts, focusing on male workers. We construct a life cycle model in which individuals decide each period whether to go to school, work, or stay non-employed. Individuals can accumulate skills either in school or while working. Wage inequality arises from differences across individuals in their ability to learn new skills as well as from idiosyncratic shocks. Progressive taxation compresses the (after-tax) wage structure, thereby distorting the incentives to accumulate human capital, in turn reducing the cross-sectional dispersion of (before-tax) wages. Consistent with the model, we empirically document that countries with more progressive labor income tax schedules have (i) significantly lower before-tax wage inequality at different points in time and (ii) experienced a smaller rise in wage inequality since the early 1980s. We then study the calibrated model and find that these policies can account for half of the difference between the US and the CEU in overall wage inequality and 84% of the difference in inequality at the upper end (log 90-50 differential). In a two-country comparison between the US and Germany, the combination of skill-biased technical change and changing progressivity of tax schedules explains all the difference between the evolution of inequality in these two countries since the early 1980s.

Section 1 presents a preliminary attempt at clarifying the ways in which taxes affect human capital accumulation. Section 2 outlines a simple general equilibrium model with two capital goods - physical and human - and the saving corresponding to each, to begin to deal with these issues. Once human capital is viewed as an alternative source of wealth and hence human capital investment as a source of current saving (re-sources withdrawn from current consumption to help increase future output), the old issue of the differential tax treatment of alternative types of capital arises. Sensible tax policy with respect to the taxation of either physical or human capital must take into account the tax treatment of the alternative asset. Section 3 outlines some points of departure for such an analysis

The highly complicated nature of modern tax codes mean economists and policy makers need simplified summary measures to understand how taxes affect the economy. Studies of what is known as the effective tax rate - that is, a measurement of the net amount of tax levied on certain economic activities - provide this sort of descriptive summary. With these estimates of effective tax rates, economists can look for evidence of how taxes affect economic behaviour and policy makers can evaluate whether the net outcome of all the different tax laws is in accord with their intentions. Globalisation, with its accompanying international mobility of capital and labor, has created a new use for estimates of the effective tax rate as policy makers seek to compare tax burdens in one country with those in another.

Economists have long recognized the importance of capital accumulation for productivity and economic growth. The National Bureau of Economic Research is currently engaged in a study of the relationship between such accumulation and taxation policies, with particular focus on saving, risk-taking, and corporate investment in the United States and abroad. The papers presented in Taxes and Capital Formation are accessible, nontechnical summaries of fourteen individual research projects within that study. Complete technical reports on this research are published in a separate volume, The Effects of Taxation on Capital Accumulation, also edited by Martin Feldstein. By addressing some of the most critical policy issues of the day with a minimum of economic jargon, Taxes and Capital Formation makes the results of Bureau research available to a wide audience of policy officials and staff as well as to members of the business community. The volume should also prove useful for courses in public policy, business, and law. In keeping with Bureau tradition, the papers do not contain policy recommendations; instead, they promote a better understanding of how the economy works and the effects of specific policies on particular aspects of the economy.