Categorize the population of a nation into three broad categories
on the basis of age composition and explain it.

The age composition of the population refers to the number of people in different age groups in a country. It is one of the most basic characteristics of a population.
The age composition of the population is expressed in three broad categories.
(i) Children below the working age (below 15 yrs) : They are economically unproductive, and need to be provided with food, clothing, education and medical care.
(ii) Persons in the working age (15 to 59 yrs): They are economically productive and biologically reproductive. They comprise the work population.
(iii) Old persons above the working age (above 59 yrs) : They can be economically productive, but need care.
Anyone, who is engaged in work and has the ability to do so is the part of the working population. The dependent population is either in the age group of below 15 years or in the age group of over 59 years.