When fewer people were required for farming, many of them migrated to cities to work in factories fueled by steam engines. Here were the centers of innovation, yielding technologies such as the steam engine, vaccines, better medicine, and better nutrition. Humans started becoming healthy, life span increased, and the earth's population touched 1 billion.

Around 350 years ago, humans began using technology in agriculture, allowing farmers to produce more food on the same amount of land. Improved nutrition led to longer life spans, which in turn contributed to an increase in the global population.

When education level increase and more women joins the work force, the average of marriage age increases, which equals less fertility rate because women who marry older usually have less children. When women do not have good access to education they tend to get married very young in order to achieve financial stability. When women get married younger in tends to result in higher fertility rates. (Mali)

In poorer countries like Mali, most women don't have access to birth control which results in them having for children/higher fertility rate.

Because of they agriculture and industrial revolutions the life expectancy has increased globally by a wide margin. The amount of babies that live pass 1(IMR) also increased, this caused the global population to go up dramatically.

When women have access to education and are empowered to pursue meaningful careers, they tend to marry later and have fewer children. In contrast, women in impoverished farming communities often have larger families to help with farm labor. Additionally, the stability of a country’s economy influences fertility rates, as a stronger economy typically leads to better job opportunities, healthcare, and education, which can result in smaller family sizes.

In some countries, such as Kenya, having large families with 5 to 9 children is culturally common. Meanwhile, in other regions like Canada, families typically consider 1 or 2 children to be the norm

If a country has a large percentage of the population in the 15-40 age group they will have a faster growth rate because those people are usually starting families.(think Mexico) If a country has a large percentage of their population in older age groups, 50+ they will have a slow growth rate(like Japan)