: Death rates fall due to better sanitation and medicine, while birth rates remain high, leading to rapid population growth.
Most modern demographic analysis is framed by the , which describes the historical shift from high birth and death rates to low ones as societies develop. Demography: The Study of Human Population
: Both rates are low; the population stabilizes. : Death rates fall due to better sanitation
: Birth rates fall below death rates, leading to an aging and potentially shrinking population—a stage now characterizing many advanced economies like Japan and Italy. while birth rates remain high
: Birth rates begin to fall as society urbanizes and education (especially for women) increases.