The natural increase rate is the birth rate minus the death rate. lt is normally expressed as a percentage per year. The natural increase rate is the rate at which the population is growing naturally, excluding gains from migration. Sometimes a country may experience a negative natural increase (called natural decrease).
A natural decrease may occur in some of the fluctuations in stages 1 and 4 of the demographic transition model
The natural population increase rate is calculated using the following formula:
Natural Population Increase Rate = (Number of Births – Number of Deaths) / Total Population x 1000
A positive natural population increase rate indicates that the number of births exceeds the number of deaths, resulting in population growth. Conversely, a negative natural increase rate means that the number of deaths exceeds the number of births, leading to population decline.
Several factors can influence the natural population increase rate, including fertility rates, mortality rates, and overall population structure. Higher fertility rates, particularly among younger age groups, contribute to a higher natural increase rate. Conversely, lower fertility rates and higher mortality rates, especially among older age groups, can lead to a lower or negative natural increase rate.
The natural population increase rate is an essential demographic indicator used by policymakers, researchers, and planners to understand population dynamics, estimate future population growth, and make informed decisions related to healthcare, education, social services, and infrastructure development. It provides valuable insights into the demographic health and trends of a population.