expand The world population will be 2 billion less than UN forecasts by 2100. This is because of the diminishing fertility rates and populations ageing in many countries. This forecast has positive and negative effects. The positive effect includes good news for the environment, while the negative effect includes shrinking workforces and inverting population pyramids which will result in poor economic condition. The study may have impacted us since it concerns our future and the future of ours children. Additionally, awareness of the population, whether it's declining or increasing, is important because it is interconnected to some fundamental aspects of our civilisation including technology, health, and the like