Global and local inequality has been a major topic of debate, leading to many attempts to quantify income disparity. The Gini Coefficient is the best-known measure of inequality, but it has its flaws, as do all inequality measurements.  
A popular measurement of economic inequality focuses on variations in income among people in a state. Since no country has perfect equality, the question becomes one of calculating how unequal a particular society is. Various formulas have been devised to measure the difference between the average income and the distribution of earnings. At the end, a single number is used to represent a nation’s level of inequality. A good index should take into account several basic rules. For example, the size of the country should not affect the level of inequality. Moreover, the absolute value of income should not change the calculated level of disparity. Finally, if income is transferred from the rich to the poor, the level of inequality should fall.