Life expectancy is a statistical measure of the average time an organism is expected to live, based on the year of their birth, their current age and other demographic factors including sex.
Gender is the range of characteristics pertaining to, and differentiating between, masculinity and femininity.
Birth, also known as parturition, is the act or process of bearing or bringing forth offspring.
Demography is the statistical study of populations, especially human beings.
My Life Expectancy by The Clairity Project
The most commonly used measure of life expectancy is at birth, which can be defined in two ways: while cohort LEB is the mean length of life of an actual birth cohort and can be computed only for cohorts born many decades ago, so that all their members died, period LEB is the mean length of life of a hypothetical cohort assumed to be exposed since birth until death of all their members to the mortality rates observed at a given year.
In the social sciences a social group has been defined as two or more people who interact with one another, share similar characteristics, and collectively have a sense of unity.
In statistics, marketing and demography, a cohort is a group of subjects with a common defining characteristic.
Death is the termination of all biological functions that sustain an organism.
Life Expectancy for Diabetes by Diabetes.co.uk
National LEB figures reported by statistical national agencies and international organizations are indeed estimates of period LEB.
In the Bronze Age and the Iron Age, LEB was 26 years; the 2010 world LEB was 67.2 years.
The Glasgow effect refers to the unexplained poor health and low life expectancy of residents of Glasgow, Scotland, compared to the rest of the United Kingdom and Europe.
The Iron Age is an archaeological era, referring to a period of time in the prehistory and protohistory of the Old World when the dominant toolmaking material was iron.
The Bronze Age is a period characterized by the use of bronze, proto-writing, and other early features of urban civilization.
For recent years, in Swaziland LEB is about 49, and in Japan, it is about 83.
Swaziland, officially the Kingdom of Swaziland, is a sovereign state in Southern Africa.
Japan is an island country in East Asia.
The combination of high infant mortality and deaths in young adulthood from accidents, epidemics, plagues, wars, and childbirth, particularly before modern medicine was widely available, significantly lowers LEB.
Infant mortality refers to deaths of young children, typically those less than one year of age.
But for those who survive early hazards, a life expectancy of 60 or 70 would not be uncommon.
For example, a society with a LEB of 40 may have few people dying at precisely 40: most will die before 30 or very few after 55.
In populations with high infant mortality rates, LEB is highly sensitive to the rate of death in the first few years of life.
Because of this sensitivity to infant mortality, LEB can be subjected to gross misinterpretation, leading one to believe that a population with a low LEB will necessarily have a small proportion of older people.
For example, in a hypothetical stationary population in which half the population dies before the age of five but everybody else dies at exactly 70 years old, LEB will be about 36, but about 25% of the population will be between the ages of 50 and 70.
Another measure, such as life expectancy at age 5, can be used to exclude the effect of infant mortality to provide a simple measure of overall mortality rates other than in early childhood; in the hypothetical population above, life expectancy at 5 would be another 65.
Aggregate population measures, such as the proportion of the population in various age groups, should also be used along individual-based measures like formal life expectancy when analyzing population structure and dynamics.
Mathematically, life expectancy is the mean number of years of life remaining at a given age, assuming age-specific mortality rates remain at their most recently measured levels.
It is denoted by
,[a] which means the mean number of subsequent years of life for someone now aged
, according to a particular mortality experience.