Editing Lorenz curve (section)

==Explanation==
{{Lorenz curve global income 2011.svg}} Data from 2005.
Points on the Lorenz curve represent statements such as, "the bottom 20% of all households have 10% of the total income."

A perfectly equal income distribution would be one in which every person has the same income.  In this case, the bottom {{nowrap|{{mvar|N}}%}} of society would always have {{nowrap|{{mvar|N}}%}} of the income.  This can be depicted by the straight line {{math|1=''y'' = ''x''}}; called the "line of perfect equality."

By contrast, a perfectly unequal distribution would be one in which one person has all the income and everyone else has none.  In that case, the curve would be at {{math|1=''y'' = 0%}} for all {{math|''x'' < 100%}}, and {{math|1=''y'' = 100%}} when {{math|1=''x'' = 100%}}. This curve is called the "line of perfect inequality."

The [[Gini coefficient]] is the ratio of the area between the line of perfect equality and the observed Lorenz curve to the area between the line of perfect equality and the line of perfect inequality. The higher the coefficient, the more unequal the distribution is. In the diagram on the right, this is given by the ratio {{math|''A'' / (''A''+''B'')}}, where {{mvar|A}} and {{mvar|B}} are the areas of regions as marked in the diagram.