Demography is the statistical study of populations of potentially any kind of animal, but it's often more specifically

applied to the study of human populations. So when we look at big groups of people and attempt

to put them into smaller groups, based on environmental circumstances like where they were

born or in what year, but also based on habits, on education, on health

and lifestyle, and birth and death statistics, that's demographic information we are collecting

and demographic groups that we are creating. Demographic information is immensely useful

when we're trying to figure out what the population of a country looks like,

and what a government might do better to serve the various groups that live within their borders.

It's also useful in terms of predicting political and consumer behavior,

and as such, a great deal of demographic research is conducted or funded by entities that are hoping

to learn more about groups of people, so they can better sell things to those people, including

political and ideological messages for which they hope to garner support. A cohort is a group of people

who share a defining characteristic within the world of demography.

So a group of people within a studied population who were all born within a particular town

might form a cohort based on that shared attribute.

A group of people who graduated in a particular year across the entire expanse of a country, likewise, would make up a cohort of

people who graduated in, let's say, the year 1990 or 1964, or 2010. You might also create a cohort

around a range rather than a specific year. This, if done correctly, can uncover some quite general but also

potentially fairly meaningful and useful trends common to a group of people whose lives have

been influenced by events and circumstances resonant with a particular age group, living in a

particular place at a particular time.

The term baby boomer in the United States, for instance,

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