The degree to which a population is replacing itself.

The resource will run out.

A total fertility rate is a measure of children per woman, and to achieve replacement level fertility, the total fertility rate must be slightly above 2.

South Korea has one of the lowest fertility rates in the world, consistently below the replacement rate of 2.1 children per woman. This low fertility rate has raised concerns about aging population and potential economic issues in the future.

Population replacement level refers to the fertility rate needed for a population to replace itself without migration, typically around 2.1 children per woman. This rate ensures the current population size is maintained over time. A fertility rate below the replacement level can lead to a declining population and various social and economic challenges.