The natural growth rate is equal to the birth rate (b) – death rate (d). Natural population growth rates can be calculated using birth and death; however, the most significant component of population growth is the longevity of members of a population. People can attribute their longevity to better nutrition, greater access to medical care, better sanitation, widespread vaccinations, increased education, and greater availability of resources based on socioeconomic advantages. As long as the birth rate is higher than the death rate, the population grows. The exponential growth of populations is visualized using a J curve. In humans, the reproductive base expands every day, because more individuals are born than die. In human populations, immigration and emigration must also be taken into account. Some regions of the world increase significantly due to the influx of immigrants, and while this event does not directly increase the total world population, it shifts gene pools and lends itself to greater growth in one area of ​​the world, while in another area