Charles,2024-05-302024-05-302012-01-17https://drs.ess.gov.et/handle/12345678/832roadly defined, demography is the study of the characteristics of populations. It provides amathematical description of how those characteristics change over time. Demographics can includeny statistical factors that influence population growth or decline, but several parameters are particularly important: population size, density, age structure, fecundity (birth rates), mortality (death rates), and sex ratio (Dodge 2006). We introduce each of these in turn.enAbstract