<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> Within the study of demography, the rate of natural increase (RNI) is classified as the crude birth rate minus the crude death rate . </P> <P> This rate gives demographers an idea of how a certain country's population is growing . RNI excludes in - migration and out - migration, giving an indication of population growth based only on births and deaths . RNI can indicate what stage of the Demographic Transition Model (DTM) a country is in . Trends in RNI can predict a country's economic stability, level of development, and other things . </P>

How is the rate of natural increase determined
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