Zero population growth (ZPG) occurs when birth rates equal death rates, resulting in no net change in the size of a particular population over time. This means that each generation replaces itself without any overall increase or decrease in numbers.
Related terms
Replacement-level fertility: The level of fertility necessary to maintain a stable population size, assuming no migration.
Demographic equilibrium: A state in which birth rates, death rates, and migration rates are balanced, resulting in no significant change to the overall population size.
Sustainable population: A population size that can be maintained over the long term without depleting resources or causing environmental degradation.