What Is a Cohort?
In marketing, the term "cohort" refers to specific experiences, events or other factors shared by a group of consumers. These cohorts are used to identify and target segments of the market that, although they may fit into other models, are more effectively grouped and treated as one.
The idea is that, although individuals make purchasing decisions, they do so based on events experienced while coming of age (late adolescence/early adulthood, or generally, when they were seventeen to twenty-three). These events, called defining moments, influence attitudes, preferences, values, and buying behaviors. And these attitudes, values, and buying-behavior motivations for each cohort remain virtually the same throughout their lives.
That’s why, for example, those who came of age during the Great Depression still are financially risk-averse and tend to “save for a rainy day” while those Baby Boomers who were teenagers during the 1960s (when economic times were good) are more likely to “buy now, pay later” even during economic slumps.
Grouping people into cohorts is not the same as segmenting them by generations, because cohorts are defined by influential societal events, which can happen at any time and shift societal values and attitudes. For example, the cohort defined most by World War II spans only six years, but the post-World War II group covers three times as many year

Cohorts Versus Demographics
Cohorts are often confused with the general demographics that are typically used to segment the marketplace. Demographic groupings such as income level or age are not considered marketing cohorts. Cohorts are the things that separate specific groups of people even within their demographic groupings. For example, men between the ages of 55 and 70 are a demographic grouping. Men between the ages of 55 and 70 who share the experience of having served in the Navy on board aircraft carriers are a cohort. Cohorts are far more specific than standard demographic groupings and as such are a valuable tool for precisely targeted marketing campaigns and niche businesses.

Events
Special events are a natural cohort, and marketing teams are quick to seize upon them for promotional gain. For example, people attending a concert of some note will often feel as though they were present for something that was meaningful in their lives. This cohort creates an opportunity to promote and sell items that commemorate the event and focus on the concert as a defining moment.

Experiences
Shared experiences can account for valuable marketing cohorts that bank on the consumer's desire to remain a part of the past. The great depression was for all its trauma and hardship an experience that shaped many people, in particular their outlook on spending and saving. People who have lived through the lean times have a better understanding that they may return at any time and they live their lives in a state of semi-preparedness as a result. Marketing professionals may use such an experience as a cohort to identify segments of the population who may be more receptive to financial products like bank accounts, gold shares or life insurance.

How to Use Cohort Information

To use cohort segmentation most powerfully, combine what you know about people’s age groups with what you know about your customers’ lifestyle choices. Examples of lifestage segments are young careerists, young families, empty-nesters, retirees, and so on. Most people follow a pretty predictable path through life stages such as these, and their purchasing behavior is likewise predictable within each life stage. (Young parents want baby paraphernalia and more living space, for example.) But each cohort brings its unique value structures as it goes through these life stages. For example, consider grandparenting, which begins typically about age fifty. Those older cohorts who suffered through the Great Depression and found satisfaction in holding the family together became nurturing grandparents. Baby Boomers, who created “latchkey children,” may well bring their tendency to keep children “at arm’s length” into their grandparenting life stage. Alternatively, they may be finding they lost much personal satisfaction in their parenting years and become doting grandparents. In either event, life-stage behavior is fashioned by the cohort values brought to that life-stage. Taking into consideration just two things—lifestyle and age cohort—you can target your product or service to the group most likely to embrace it.
You can use this information to:
• develop new products to meet the unique and unmet needs of a group.
• reposition your brand to appeal to a specific group.
• craft communications to resonate with a cohort’s core values on an emotional level.(For example: Toyota created the spin-off brand Scion specifically to appeal to young adults. Scion car ads use language and show images emphasizing fun and freedom, since those are core values of this age cohort.)
• plan how your marketing should change as your target age cohort moves through the life stages. (Example: Gap started by marketing clothing to teenagers, but as that cohort grew older, added branches for Baby Gap and Gap Kids. Yet they still reflect Generation-X values in product offerings and in the style of their promotional material.)
• choose images, sounds, and spokespersons identified with a cohort to tap feelings of nostalgia from when they came of age.
Cohorts do not open doors for the marketing of all products. The marketing of motor oil, retractable pens, and potting soil do not seem to require an understanding of cohort values. Marketing to specific cohorts is especially effective, however, for those selling food, music, clothing, cars, financial services, insurance, and entertainment products

Drawbacks
For all their marketing value, cohorts do have significant drawbacks. They are often too precise for most companies to use as a general marketing tool and can only be employed in cases where extreme drilling down of marketing methods and approaches are warranted. If your company handles the litigation for a specific type of illness contracted in a specific place and time, cohort marketing is the way to go. If you are advertising a general legal practice, there are better ways to reach a broader audience. The costs involved with collecting, then organizing the very specific data required to segment cohorts are also often prohibitive for many companies.