How GNI per capita and life expectancy relate across countries, and where individual countries depart from the overall pattern.
National income and life expectancy are often examined together.
Each dot represents a country. The horizontal axis shows GNI per capita (gross national income per person, adjusted for purchasing power). The vertical axis shows life expectancy at birth.
Across countries, higher income levels tend to appear alongside higher life expectancy, though the relationship is not uniform — countries can differ from the overall pattern in either direction.
A log scale makes the relationship easier to see.
GNI per capita ranges from under $1,000 to well over $100,000 across countries, so a linear scale compresses most countries into a narrow band. Switching the horizontal axis to a log scale spreads out lower- and middle-income countries and makes the overall pattern easier to follow.
The fitted line summarizes the overall relationship between income and life expectancy across all countries.
Some countries sit above or below the overall fitted relationship.
Nicaragua (GNI per capita $7,640; life expectancy 77 years) and Costa Rica ($25,800; 81 years) sit above the overall pattern — their life expectancy is higher than the fitted relationship would suggest for their income level. Guyana ($50,060; 70 years) and the United States ($82,190; 78 years) sit below it.
Countries at similar income levels can still have different life expectancy outcomes.