DEFINITION of 'Quintiles'
A statistical value of a data set that represents 20% of a given population. The first quartile represents the lowest fifth of the data (120%); the second quartile represents the second fifth (21%  40%) etc.
INVESTOPEDIA EXPLAINS 'Quintiles'
Quintiles are often used to create cutoff points for a given population. For example, a government sponsored socioeconomic study may use quintiles to determine the maximum wealth a family could possess in order to belong to the lowest quintile of society. This cutoff point can then be used as a prerequisite for a family to receive a special government subsidy aimed to help society's less fortunate.
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