The percentage of the population that falls below the poverty line is called the:

The answer is the Poverty Rate.

Explanation:

Poverty rate means that the income that comes from a family household is below the Poverty Line. This is usually a calculation in which a specific percentage of people are placed in this category.

The federal government usually tries to regulate this line and this one can change according to the family's size as well as the changes that can occur on the level of price. An important aspect referring to the poverty rate is that if two countries share the same poverty rates it could be a difference regarding the relative income-level of the poor.  

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