What is 'life expectancy at birth' and why is it significant?

• A. The age at which people start to have children.
• B. The average number of years a newborn is expected to live; a key measure of development and health.
• C. The median age of the population.
• D. The age at which a person leaves the workforce.

Answer: (B)

Life expectancy at birth is the average number of years a newborn is expected to live if current mortality rates stay the same throughout their life. This measure is significant because it serves as a broad gauge of a population’s overall health and development, reflecting factors like healthcare quality, sanitation, nutrition, and disease burden. It helps compare how well countries are doing and tracks changes over time, guiding policy and resource allocation.

The other ideas describe different concepts: the age people typically start having children, the median age of the population, or the age people retire. None of these capture the expected lifespan of a newborn, which is what life expectancy at birth measures.