How many years does a generation have?

Question

before it is sealed into the chambers of history as a living relic.

Answer 1

A generation has traditionally been defined as “the average interval of time between the birth of parents and the birth of their offspring." This makes a generation around 30 years in length. However, while this rule of thumb has served sociologists well in analysing generations up to and including the Baby Boomers, it is less relevant for recent generations.

Firstly, because cohorts are changing so quickly in response to new technologies, changing career and study options, and because of shifting societal values, their characteristics can change in less than two decades. Secondly, the time between birth of parents and birth of offspring has stretched out from two decades to more than three. Looking at Australian statistics, the median age of a woman having her first baby was 24 in 1976, while today it is just over 30. So, while the Boomers are the children of the Builders or Veterans, Gen Z are often the younger siblings of Gen Y – or the children of the late-breeding Gen X. In recent years, the median age of first-time mothers throughout the western world has reached record highs.

USA - 25.2 years

UK - 27.4 years

Answer 2

About 30-35 years traditionally.  However, people are getting married much later and women are having babies much later, so that number will probably stretch out.

Answer 3

Years ago, I was part of a population genetics study of pre-19th C. and we came up with a generation of around 26 years.

Your question is broader, but this figure is still relevant because part of the answer is the question: when does the generation move to position of cultural influence, and when is it less influential because of the presence of new generational cohorts.

There used to be a concept in Europe (around 13th-19th C) of the "age of Christ" - that is Christ was around 30-35 YO when he changed the world. More generically, that is a typical age when energy and accomplishment, material wealth and freedom of action come together to allow potential.  So people (especially men with education and position, of course) reaching that age would be expected to ask themselves, what will be my mark on the world?

The other part of the answer is another question: how much does youth respect age? That varies a bit age to age and culture to culture.

Answer 4

The traditionally accepted figure has been 30 years -- the period of time between one woman giving birth and her child giving birth. Recent years ave seen a slight increase in this span because of the number of women who delay pregnancy because of career. Conversely, it is somewhat lower in less industrialized regions.