In economics, the Gini coefficient, also known as the Gini index or Gini ratio, is a measure of statistical dispersion intended to represent the income inequality, the wealth inequality, or the consumption inequality within a nation or a social group. It was developed by Italian statistician and sociologist Corrado Gini.
Economic inequality is an umbrella term for a) income inequality or distribution of income, b) wealth inequality or distribution of wealth, and c) consumption inequality. Each of these can be measured between two or more nations, within a single nation, or between and within sub-populations.
In economics, income distribution covers how a country's total GDP is distributed amongst its population. Economic theory and economic policy have long seen income and its distribution as a central concern. Unequal distribution of income causes economic inequality which is a concern in almost all countries around the world.
Income inequality metrics or income distribution metrics are used by social scientists to measure the distribution of income and economic inequality among the participants in a particular economy, such as that of a specific country or of the world in general. While different theories may try to explain how income inequality comes about, income inequality metrics simply provide a system of measurement used to determine the dispersion of incomes. The concept of inequality is distinct from poverty and fairness.
The distribution of wealth is a comparison of the wealth of various members or groups in a society. It shows one aspect of economic inequality or economic heterogeneity.
International inequality refers to inequality between countries, as compared to global inequality, which is inequality between people across countries. International inequality research has primarily been concentrated on the rise of international income inequality, but other aspects include educational and health inequality, as well as differences in medical access. Reducing inequality within and among countries is the 10th goal of the UN Sustainable Development Goals and ensuring that no one is left behind is central to achieving them. Inequality can be measured by metrics such as the Gini coefficient.
Income inequality has fluctuated considerably in the United States since measurements began around 1915, moving in an arc between peaks in the 1920s and 2000s, with a 30-year period of relatively lower inequality between 1950 and 1980.
Income in India discusses the financial state in India. With rising economic growth and prosperity, India's income is also rising rapidly. As an overview, India's per capita net national income or NNI was around 9.97 lakh rupees in 2022. The per-capita income is a crude indicator of the prosperity of a country. In contrast, the gross national income at constant prices stood at over 128 trillion rupees. The same year, GRI growth rate at constant prices was around 6.6 percent. While GNI and NNI are both indicators for a country's economic performance and welfare, the GNI is related to the GDP or the Gross Domestic Product plus the net receipts from abroad, including wages and salaries, property income, net taxes and subsidies receivable from abroad. On the other hand, the NNI of a country is equal to its GNI net of depreciation.
The inequality of wealth has substantially increased in the United States in recent decades. Wealth commonly includes the values of any homes, automobiles, personal valuables, businesses, savings, and investments, as well as any associated debts.
Income inequality in the Philippines is the extent to which income, most commonly measured by household or individual, is distributed in an uneven manner in the Philippines.
China's current mainly market economy features a high degree of income inequality. According to the Asian Development Bank Institute, “before China implemented reform and opening-up policies in 1978, its income distribution pattern was characterized as egalitarian in all aspects.”
Brazil has been tackling problems of income inequality despite high rates of growth. Its GDP growth in 2010 was 7.5%. In recent decades, there has been a decline in inequality for the country as a whole. Brazil's GINI coefficient, a measure of income inequality, has slowly decreased from 0.596 in 2001 to 0.543 in 2009. However, the numbers still point to a rather significant problem of income disparity.
Tax policy and economic inequality in the United States discusses how tax policy affects the distribution of income and wealth in the United States. Income inequality can be measured before- and after-tax; this article focuses on the after-tax aspects. Income tax rates applied to various income levels and tax expenditures primarily drive how market results are redistributed to impact the after-tax inequality. After-tax inequality has risen in the United States markedly since 1980, following a more egalitarian period following World War II.
Poverty in New Zealand deals with the incidence of relative poverty in New Zealand and its measurement. Between 1982 and 2011, New Zealand's gross domestic product grew by 35%. Almost half of that increase went to a small group who were already the richest in the country. During this period, the average income of the top 10% of earners in New Zealand almost doubled going from $56,300 to $100,200. The average income of the poorest tenth increased by only 13% from $9700 to $11,000. Figures from 2016 show that about 15% of the population lives in poverty, compared to 9% in the 1980s, and 22% in 2004.
Sweden enjoys a relatively low income inequality and a high standard of living. Unemployment as of 2017 was estimated to be 6.6% by the CIA World Fact Book, lower than in other European Union countries. The Nordic model of a social welfare society exemplified by Sweden and its near neighbours has often been considered a European success story compared internationally with the socioeconomic structures of other developed industrial nations. This model of state provided social welfare includes many unemployment benefits for the poor, and amply funded health, housing and social security provision. within essentially corruption free nations subscribing to principles of a measure of openness of information about government activity. The Income inequality in Sweden ranks low in the Gini coefficient, being 25.2 as of 2015 which is one of the lowest in the world, and ranking similarly to the other Nordic countries; although inequality has recently been on the rise and several central European countries now have a lower Gini coefficient than Sweden.
World Inequality Database (WID), previously The World Wealth and Income Database, also known as WID.world, is an extensive, open and accessible database "on the historical evolution of the world distribution of income and wealth, both within countries and between countries".
Since the turn of the millennium, China has become the fastest growing economy in the world. This growth resulted in significant improvements in real living standards and reduction in poverty rates. The World Bank estimates that more than 60% of the population lived below the poverty line of $1 per day (PPP) at the start of the economic reforms. By 2004, poverty had fallen to 10 percent, suggesting that approximately 500 million people had been lifted out of poverty in one generation. At the same time, the pace of change has brought mixed results. China faces serious natural resource shortages and environmental problems. As people live in different areas, the differences between types grow.
