There are various reasons for thisvariation in the trend of population growth rate in various censuses. There aremany factors that encourages the growth rate of population.
The causes ofpopulation explosion include migration, birth rate and death rate, and so on. One of main reason for the population increaseis improvements in industries, technology, and availability of medicalfacilities science and medicine. The health conditions and improvement incontrolling of disease that enables people to decrease in infant mortalityrate. As a result, there is decrease in old people and no decrease in youngpeople. Another factor leads to lower death of rate is that abortion is notallowed by several religions in India, and the availability of medicalfacilities enables women to increase birth through medical with preventivedrugs such as vaccine. Moreover, there is rapid rise in the standard of living that leads toincrease in life expectancy.
Thehigh population growth rates are due toimproved living conditions, better sanitation, better nutrition, healtheducation, etc. the average life expectancy of human population has improvedsignificantly. Also, an increase in immigration often contributes towardspopulation explosion, particularly in developed countries. It happens when alarge number arrive at an already populated place with the intention to residepermanently. Lastly, due to lack of awareness about the positive impact ofusing birth-control method, there has been a steady growth in birthrate.