Population projections are generally an estimate of what the population will look like in future.
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specifically, projections are an educated guess of the population size and structure based on
assumptions about future population trends and analyses of current and historical trends. Population projections are conditional and the resulting figures are dependent on the underlying assumptions.
1. Projections help in planning i.e.- Allocation of resources
- Assessment of the needs of population subgroups e.g. children, the elderly
- Raising awareness of existing/impending challenges
2. Projections help in the formulation of relevant and effective policies i.e.
- Identification of priority areas
- Putting in place measures to address impending challenges beforehand
The techniques for population projections can be used beyond estimating population sizes. For instance, we can project how many covid-19 cases would be recorded by a certain time. We tweeted a projection earlier illustrating what Ghana's case count could look like at the end of July.
A recent study estimated that adherence to social distancing could reduce covid-19 transmission by 82%. In the graph above, we estimated Ghana's case count in the alternate scenario where the projected numbers are reduced by 20%. We use a very conservative percentage that is a quarter of the 80% from the study to be more realistic for the context and current climate. We see that about 7,000 new cases could be averted this month if more social distancing was observed.