Life Expectancy at Birth
Definition
The average number of years a newborn infant would live if current mortality rates at each age remain constant throughout their life. It is the most widely used summary measure of population health.
Why It Matters
Life expectancy reflects overall health system quality, nutrition, sanitation, safety, and economic development. It is used to compare health outcomes across countries and track progress over time.
How It's Measured
Calculated from age-specific death rates using actuarial life tables. Published by the WHO, World Bank, and national statistics agencies.
Current Value
US: approximately 77.5 years; Japan (highest): approximately 84.8 years
Related Ranking
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Frequently Asked Questions
The average number of years a newborn infant would live if current mortality rates at each age remain constant throughout their life. It is the most widely used summary measure of population health.
Life expectancy reflects overall health system quality, nutrition, sanitation, safety, and economic development. It is used to compare health outcomes across countries and track progress over time.
Calculated from age-specific death rates using actuarial life tables. Published by the WHO, World Bank, and national statistics agencies.