Preston Curve | 05 Jun 2024
The Preston curve refers to the empirical relationship between life expectancy and per capita income in a country, proposed by American sociologist Samuel H. Preston in 1975.
- The curve shows that people in richer countries generally have longer life spans compared to those in poorer countries, likely due to better access to healthcare, education, nutrition, etc.
- As a poor country's per capita income rises, its life expectancy increases significantly initially.
- For example, India's per capita income rose from Rs 9,000 in 1947 to
- Rs 55,000 in 2011, while life expectancy increased from 32 to 66 years.
- However, the positive relationship between per capita income and life expectancy starts to flatten out beyond a certain point, as the human lifespan cannot be increased indefinitely.
- The positive relationship shown by the Preston curve applies can also be applied to other development indicators like infant/maternal mortality, education, healthcare, etc.