Generational cohorts

A generational cohort has been defined as "the group of individuals (within some population definition) who experience the same event within the same time interval". The notion of a group of people bound together by the sharing of the experience of common historical events developed in the early 1920s. Today the concept has found its way into popular culture through well known phrases like "baby boomer" and "Generation X".

The United Kingdom has a series of four national birth cohort studies, the first three spaced apart by 12 years: the 1946 National Survey of Health and Development, the 1958 National Child Development Study, the 1970 British Cohort Study, and the Millennium Cohort Study, begun much more recently in 2000. These have followed the lives of samples of people (typically beginning with around 17,000 in each study) for many years, and are still continuing. As the samples have been drawn in a nationally representative way, inferences can be drawn from these studies about the differences between four distinct generations of British people in terms of their health, education, attitudes, childbearing and employment patterns. The last three are run by the Centre for Longitudinal Studies

Most demographic information is also culturally based. The generational cohort information above, for example, applies primarily to North America (and to a lesser extent to Western Europe) and it may be unfruitful to generalize conclusions more widely as different nations face different situations and potential challenges.