The natural increase rate does not consider immigration or emigration. It is determined by subtracting the number of deaths from the number of births in a given region. So, if there are ten thousand deaths and thirteen thousand births in a given region, in a given time period, the natural increase rate is three thousand.

The stationary population level (SPL) is the level at which a population cannot grow any more.

During the past half-century much of the developed world has experienced a process known as deindustrialization -factories and manufacturing centers have closed down in the United States of America, Western Europe, and Japan and those jobs have been outsourced to the developing world. This has led to the rise of “service-based economies” in the developed world. A “service-based economy” is an economy in which most of the workers are involved in providing services such as research, marketing, telecommunications, innovation, teaching, and so on.

An Essay on the Principle of Population, published at the end of the eighteenth century, was written by Thomas Malthus. In this essay, Malthus argues that the rate of food production grows arithmetically, whereas population grows exponentially. Malthus argued that this would lead to a situation where population outstrips food production, leading to widespread famine and starvation. His writings are extremely influential even to this day; however, many geographers dispute his conclusions and argue that technology augments food production, allowing it to keep up with population growth. It remains to be seen whether Malthus’ predictions will come true in the twenty-first century or beyond.

Housing in urban centers was actually more expensive than housing in rural areas, due to the high value of land. Since cities are much more densely populated than rural areas, the competition for land is greater, driving up the cost of housing.

All of these countries are in either stage two or stage three (the transitional stages) of the demographic transition model, except Japan, which is in stage four. Stage four is generally considered the final stage of the demographic transition model. In stage four, the birth rates and the death rates are both low and generally steady. In Japan, the death rate is very low and the birth rate is very low, leading to a steady population and perhaps even a slight population decline.

The Industrial Revolution brought former farmers into the cities to work in factories. These farmers used to grow food for themselves and their families and now needed other ways to get food. Canning foods was a simple solution that made it possible for cities to have access to food.

The crude death rate or CDR is the ratio of the number of deaths yearly per 1,000 people in a given population.

The stationary population level (SPL) is the level at which a population cannot grow any more.

Most geographers and demographers agree that over the course of the twenty-first century, the population growth will slow considerably. This is based on the belief that the current rapid population growth is an anomaly in Earth’s history and that the planet cannot sustain such rapid growth for another century.