Answer: income quintile
Explanation:
An income quintile is how the socioeconomic status of a population is measured. Here, the population is divided into 5 income groups which is from the lowest income group to the highest income group. One-fifth of the population are in each group, which is rank ordered by income.
The first quintile = 0 - 20%
Second quintile = 20% - 40%
Third quintile = 40% - 60%
Fourth quintile = 60% - 80%
Fifth quintile = 80% - 100%