Income taxAn income tax is a tax imposed on individuals or entities (taxpayers) in respect of the income or profits earned by them (commonly called taxable income). Income tax generally is computed as the product of a tax rate times the taxable income. Taxation rates may vary by type or characteristics of the taxpayer and the type of income. The tax rate may increase as taxable income increases (referred to as graduated or progressive tax rates). The tax imposed on companies is usually known as corporate tax and is commonly levied at a flat rate.
External debtA country's gross external debt (or foreign debt) is the liabilities that are owed to nonresidents by residents. The debtors can be governments, corporations or citizens. External debt may be denominated in domestic or foreign currency. It includes amounts owed to private commercial banks, foreign governments, or international financial institutions such as the International Monetary Fund (IMF) and the World Bank. External debt measures an economy's obligations to make future payments and, therefore, is an indicator of a country's vulnerability to solvency and liquidity problems.
SustainabilitySustainability is a social goal for people to co-exist on Earth over a long time. Specific definitions of this term are disputed and have varied with literature, context, and time. Experts often describe sustainability as having three dimensions (or pillars): environmental, economic, and social, and many publications emphasize the environmental dimension. In everyday use, sustainability often focuses on countering major environmental problems, including climate change, loss of biodiversity, loss of ecosystem services, land degradation, and air and water pollution.
Zero interest-rate policyZero interest-rate policy (ZIRP) is a macroeconomic concept describing conditions with a very low nominal interest rate, such as those in contemporary Japan and in the United States from December 2008 through December 2015. ZIRP is considered to be an unconventional monetary policy instrument and can be associated with slow economic growth, deflation and deleverage. Under ZIRP, the central bank maintains a 0% nominal interest rate. The ZIRP is an important milestone in monetary policy because the central bank is typically no longer able to reduce nominal interest rates.
Optimal controlOptimal control theory is a branch of mathematical optimization that deals with finding a control for a dynamical system over a period of time such that an objective function is optimized. It has numerous applications in science, engineering and operations research. For example, the dynamical system might be a spacecraft with controls corresponding to rocket thrusters, and the objective might be to reach the moon with minimum fuel expenditure.
Greek government-debt crisisGreece faced a sovereign debt crisis in the aftermath of the financial crisis of 2007–2008. Widely known in the country as The Crisis (I Krísi), it reached the populace as a series of sudden reforms and austerity measures that led to impoverishment and loss of income and property, as well as a small-scale humanitarian crisis. In all, the Greek economy suffered the longest recession of any advanced mixed economy to date. As a result, the Greek political system has been upended, social exclusion increased, and hundreds of thousands of well-educated Greeks have left the country.
Capital structureIn corporate finance, capital structure refers to the mix of various forms of external funds, known as capital, used to finance a business. It consists of shareholders' equity, debt (borrowed funds), and preferred stock, and is detailed in the company's balance sheet. The larger the debt component is in relation to the other sources of capital, the greater financial leverage (or gearing, in the United Kingdom) the firm is said to have.
Sengoku periodThe Sengoku period is the period in Japanese history in which civil wars and social upheavals took place almost continuously in the 15th and 16th centuries. Though the Ōnin War (1467) is generally chosen as the Sengoku period's start date, there are many competing historiographies for its end date, ranging from 1568, the date of Oda Nobunaga's march on Kyoto, to the suppression of the Shimabara Rebellion in 1638, deep into what is traditionally considered the Edo period.
DeleveragingAt the micro-economic level, deleveraging refers to the reduction of the leverage ratio, or the percentage of debt in the balance sheet of a single economic entity, such as a household or a firm. It is the opposite of leveraging, which is the practice of borrowing money to acquire assets and multiply gains and losses. At the macro-economic level, deleveraging of an economy refers to the simultaneous reduction of debt levels in multiple sectors, including private sectors and the government sector.
Bellman equationA Bellman equation, named after Richard E. Bellman, is a necessary condition for optimality associated with the mathematical optimization method known as dynamic programming. It writes the "value" of a decision problem at a certain point in time in terms of the payoff from some initial choices and the "value" of the remaining decision problem that results from those initial choices. This breaks a dynamic optimization problem into a sequence of simpler subproblems, as Bellman's “principle of optimality" prescribes.
Muromachi periodThe Muromachi period or Muromachi era, also known as the Ashikaga period or Ashikaga era, is a division of Japanese history running from approximately 1336 to 1573. The period marks the governance of the Muromachi or Ashikaga shogunate ( or ), which was officially established in 1338 by the first Muromachi shōgun, Ashikaga Takauji, two years after the brief Kenmu Restoration (1333–1336) of imperial rule was brought to a close. The period ended in 1573 when the 15th and last shogun of this line, Ashikaga Yoshiaki, was driven out of the capital in Kyoto by Oda Nobunaga.
Sustainable agricultureSustainable agriculture is farming in sustainable ways meeting society's present food and textile needs, without compromising the ability for current or future generations to meet their needs. It can be based on an understanding of ecosystem services. There are many methods to increase the sustainability of agriculture. When developing agriculture within sustainable food systems, it is important to develop flexible business process and farming practices.