The United States of America is a federal republic with autonomous state and local governments. Taxes are imposed in the United States at each of these levels. These include taxes on income, payroll, property, sales, imports, estates and gifts, as well as various fees. In 2010 taxes collected by federal, state and municipal governments amounted to 24.8% of GDP. In the OECD, only Chile and Mexico taxed less as a share of GDP. The United States also has one of the most progressive tax systems in the industrialized world.
Taxes are imposed on net income of individuals and corporations by the federal, most state, and some local governments. Citizens and residents are taxed on worldwide income and allowed a credit for foreign taxes. Income subject to tax is determined under tax accounting rules, not financial accounting principles, and includes almost all income from whatever source. Most business expenses reduce taxable income, though limits apply to a few expenses. Individuals are permitted to reduce taxable income by personal allowances and certain nonbusiness expenses, including home mortgage interest, state and local taxes, charitable contributions, and medical and certain other expenses incurred above certain percentages of income. State rules for determining taxable income often differ from federal rules. Federal tax rates vary from 10% to 39.6% of taxable income. State and local tax rates vary widely by jurisdiction, from 0% to 13.30%, and many are graduated. State taxes are generally treated as a deductible expense for federal tax computation. In 2013, the top marginal tax rate for a high-income California resident would be 52.9%. Certain alternative taxes may apply.
Public finance is the study of the role of the government in the economy. It is the branch of economics which assesses the government revenue and government expenditure of the public authorities and the adjustment of one or the other to achieve desirable effects and avoid undesirable ones.
The purview of public finance is considered to be threefold: governmental effects on (1) efficient allocation of resources, (2) distribution of income, and (3) macroeconomic stabilization.
Public economics (or economics of the public sector) is the study of government policy through the lens of economic efficiency and equity. At its most basic level, public economics provides a framework for thinking about whether or not the government should participate in economics markets and to what extent its role should be. In order to do so, microeconomic theory is utilized to assess whether the private market is likely to provide efficient outcomes in the absence of governmental interference. Inherently, this study involves the analysis of government taxation and expenditures. This subject encompasses a host of topics including market failures, externalities, and the creation and implementation of government policy. Public economics builds on the theory of welfare economics and is ultimately used as a tool to improve social welfare.
Broad methods and topics include:
Lucky duckies is a term that was used in Wall Street Journal editorials starting on 20 November 2002 to refer to Americans who pay no federal income tax because they are at an income level that is below the tax line (after deductions and credits). The term has outlived its original use to become a part of the informal terminology used in the tax reform debate in the United States.
The Journal defined the term in this way:
In the United States, a tax is imposed on income by the federal, most state, and many local, governments. The income tax is determined by applying a tax rate, which may increase as income increases, to taxable income as defined. Individuals and corporations are directly taxable, and estates and trusts may be taxable on undistributed income.
Partnerships are not taxed, but their partners are taxed on their shares of partnership income. Residents and citizens are taxed on worldwide income, while nonresidents are taxed only on income within the jurisdiction. Several types of credits reduce tax, and some types of credits may exceed tax before credits. An alternative tax applies at the federal and some state levels.
A federation (Latin: foedus, foederis, 'covenant'), also known as a federal state, is a political entity characterized by a union of partially self-governing states or regions under a central (federal) government. In a federation, the self-governing status of the component states, as well as the division of power between them and the central government, are typically constitutionally entrenched and may not be altered by a unilateral decision of either party, the states or the federal political body.
The governmental or constitutional structure found in a federation is known as federalism. It can be considered the opposite of another system, the unitary state. Germany with sixteen Länder is an example of a federation, whereas neighboring Austria and its Bundesländer was a unitary state with administrative divisions that became federated, and neighboring France by contrast has always been unitary.