A common measurement used in discussions of human population growth is the total fertility rate (TFR). This is the average number of children that a woman in a particular population will have. Typically, the higher the TFR, the more rapid the population growth.

There are a variety of factors that can influence the TFR of a population, with development of a country being one of the largest. Richer, more developed countries have lower TFRs and therefore lower population growth rates. As there are more educational and economic opportunities for women, as well as increased access to contraceptives, women tend to have kids later in life, resulting in fewer births overall.

There are government policies that can influence the TFR as well, such as China's two child policy, tax incentives for having fewer children, and even countries that engage in forced sterilization. Some countries are beginning to reverse course and offer tax incentives to have children due to the TFR being below the replacement level fertility.

If the TFR is equal to the replacement level fertility, births are offsetting deaths and the population is relatively stable.

The infant mortality rate (IMR) is the number of deaths of children under the age of one per 1,000 people in a population. It is higher in less developed countries due to lack of access to adequate health care, stable food supplies, and clean water. A higher IMR results in a higher replacement level fertility, which typically results in a higher TFR.

Just like other species, we have limiting factors that impart a carrying capacity on us. Malthusian theory dictates that the human population is growing faster than our food production capabilities are increasing and warns of a catastrophe once we pass this point. If we exceed our carrying capacity, there will be famines, as well as likely wars over resources.

While technological advancements, such as the invention of synthetic fertilizers or the production of high-yield GMO crops, have increased our carrying capacity by singificantly increasing food production, we still are influenced by a variety of limiting factors. Major storms, heat waves and droughts are density-independent factors that are witnessed throughout the world, and are becoming increasingly more common as climate change worsens. Access to clean water and air, food availability, available land, and disease transmission are all density-dependent factors that continue to be stretched thin or threatened as our population grows and we live unsustainably.

The standard of living is the overall measure of the quality of life for people in a population. It consists of two major parts: GDP and life expectancy.

GDP (the Gross Domestic Product) is a key economic indicator as it relates to the total value of foods and services provided. The life expectancy is a key health indicator as it relates to the average age a person in the population will live to and increases with better healthcare, cleaner water, and more stable food sources.

A higher GDP and higher life expectancy are both associated with development of a country and lower population growth.