Statistical Misreadings
Statistical data, especially comparing only two sets of figures, can show an incorrect population trend. A nation's population could be increasing, but an one-off event could have resulted in decline and vice-versa. Nations can acquire territory or lose territory and people, consider people citizens they previously denied citizenship to, e.g. stateless persons, indigenous people, and undocumented immigrants or long stay foreign residents. Political instability can render an area within a nation's count unreliable for comparison.
A common misreading is due to time. Populations on the verge of decline could rise in summer and decline in winter as deaths increase in winter in cold regions, similarly, census dates over too long a time range could show a rise when a country has already tipped into decline. Therefore, numerous sets of statistics should be interpreted to get an idea of a trend.
Read more about this topic: Population Decline