Why is it important to know about the size of different age groups,like the percent of the population under 15

Question

In A Country's Population!

Answer 1

One of the reasons this is important is because it lets you estimate the populations growth. If the majority of people are under the age of 15 you can expect a population boom when these children reach reproductive age. You also know that you have more people entering the work force than leaving. If you have the majority of a population in the upper ages, say over 65, then you know your population size is shrinking in general, and that the working force is dwindling allowing for little support to the older generations. There are lots of things you can infer from this type of data, I've only listed a couple.