<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (February 2009) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (February 2009) (Learn how and when to remove this template message) </Td> </Tr> <P> In demographics, the rate of natural increase (RNI) is the crude birth rate minus the crude death rate . This rate excludes population increase from in migration and out migration . When looking at countries, it gives an idea of what position in the Demographic Transition Model, but to find out how much a country is growing, the population growth rate should be observed . The Demographic Transition Theory explains the rate of natural increase relate to the economic growth . </P> <P> Usually developing countries have a positive or high natural increase rate . Developed countries have a negative / neutral or low natural increase rate, but many developed countries have their population increasing due to immigration despite their negative RNI . These countries also have the lower rate of death . This is because developing countries and developed countries are in different stages of the demographic transition . Developing countries are generally in the earlier stages of the transition meaning they have high fertility, which would show an increase in crude birth rates . Developed countries usually have lower or more stable fertility rates so they don't show as high rates in natural increase . This can be applied to mortality rates as well, because developing countries generally have higher mortality rates than developed countries . High mortality rates are due to differences in deaths from chronic and acute diseases . </P>

When calculating the rate of natural increase one does not include