Life expectancy is how long a person is expected to live. It is based on many factors such as country and life style including smoking, diet, and exercise.
CIA World Factbook 2008 Estimates for Life Expectancy at birth (years).
| over 80 77.5-80 75-77.5 72.5-75 70-72.5 67.5-70 65-67.5
|| 60-65 55-60 50-55 45-50 40-45 under 40 not available
There are great changes in life expectancy between different parts of the world, mostly caused by differences in public health, medical care and diet. Much of the excess mortality (higher death rates) in poorer nations is due to war, not enough food, and medical conditions or diseases (AIDS, Malaria, etc.).
Over the past 200 years, countries with African populations have generally not had the same improvements in mortality rates that have been enjoyed by other peoples.
Climate may also have an effect, and the way data is collected may also influence the figures. According to the CIA World Factbook, Macau has the world's longest life expectancy of 84.4 years.
There are also significant differences in life expectancy between men and women in most countries, with women typically outliving men by around five years. Economic circumstances also affect life expectancy. For example, in the United Kingdom, life expectancy in the expensive areas like Kensington is several years longer than in the poorest areas such as Glasgow. This may reflect factors such as diet and lifestyle as well as access to medical care. It may also reflect a selective effect: people with chronic life-threatening illnesses are less likely to become wealthy or to live in expensive areas.
Images for kids
Life expectancy in USA, China and Russia, 1960–2020
Life expectancy in the largest European countries, 1960–2020
Life expectancy at birth, measured by region, between 1950 and 2050
Life expectancy in 1800, 1950, and 2015 – visualization by Our World in Data
Plot of life expectancy vs. GDP per capita in 2009. This phenomenon is known as the Preston curve.
Life expectancy is higher in rich countries with low economic inequality
Life expectancy vs healthcare spending of rich OECD countries.
Pink: Countries where females life expectancy at birth is higher than males. Blue: A few countries in the south of Africa where females have shorter lives due to AIDS
A survival tree to explain the calculations of life-expectancy. Red numbers indicate a chance of survival at a specific age, and blue ones indicate age-specific death rates.