How Many People Live In The World?
The world's population today is approximately 7.6 billion. Of the individuals currently living, the average age is approximately 30.1 years. Just over a quarter of the population is under 15 years old. Individuals between 15 and 64 years of age make up 65.9% of the population, and another 7.9% are 65 or older. The World Health Organization suggests that the global average life expectancy is 70.5 years, with men living to 68 and women to 73 years of age. The global fertility rate is around 2.52 children per woman.
History Of Population Growth
The human population began to increase significantly at the same time agriculture was discovered, around 10,000 BC. At this time in history, the world's population was somewhere between 1 and 15 million. By the 4th century BC, between 50 million and 60 million people were alive in the Roman Empire alone. As the world's population continued to grow, illnesses plagued and wiped out large quantities of people. For example, between the years 500 and 800 AD, the Justinian Plague killed roughly half of the European population. By the time of the 14th century, humans had recovered and numbered around 450 million worldwide. However, the Black Plague took approximately 100 million lives in the year 1400 AD. Two centuries had passed before the population recovered from its losses of the Black Plague.
The Agricultural and Industrial Revolutions between the 18th and 20th centuries promoted the next great period of population growth. During this time, hygiene practices improved, vaccines were created, and life expectancies grew. By 1804, the world population had reached 1 billion for the first time. Since then, the population of the world has grown exponentially, hitting the 2 billion mark in 1927, the 3 billion mark in 1960, the 4 billion mark in 1974, the 5 billion mark in 1987, 6 billion in 1999, and finally, the 7 billion mark in 2011.
The Most Populated Countries And Cities
The continent of Asia is home to 60% of the world’s population and hosts the top 2 most populated countries in the world, China and India. Together, these two countries hold 37% of the world’s population.
China has a population of over 1.38 billion. In China, there are 12.37 births for every 1,000 people in the population and only 7.16 deaths per 1,000. The life expectancy in the country is 75.35 years. Approximately 73.4% of the population is between 15 and 64 years of age. The fertility rate is 1.55 children per woman.
In India, the population numbers a little over 1.33 billion. This number represents 18% of the world’s population. The most populated city in this country is Mumbai with over 12.44 million individuals. Delhi is the second most populated and has a population of 11,034,555. In India, the birth rate is 19.3 for every 1,000 people while there are 7.3 deaths per 1,000. The life expectancy in this country is 68.89 years of age. Around 63.6% of the population is between 15 and 64 years of age. The fertility rate is 2.3 children per woman.
The third most populated country in the world is the United States. It has a total population of around 324,707,000. The most populated city in this country is New York City with 8.55 million people. In this country, there are 13.42 births for every 1,000 people and 8.15 deaths per 1,000. The life expectancy is around 79.56 years. Around 66.2% of the population is between 15 and 64 years old. The fertility rate is 1.84 children per woman.
The Fastest Growing Populations
The fastest growing populations in the world are located in sub-Saharan Africa, the Middle East, and Latin America. This does not mean these geographic regions have the highest populations, just that they are growing more quickly than other regions around the world. Currently, the global growth percentage is around 1.14% which is down from 2.19% in the 1960’s.
According to UN estimates, however, the following countries are growing much faster than that. The top 5 countries with the fastest growing populations are Oman (8.45% growth), Lebanon (5.99%), Kuwait (4.81%), Qatar (4.72%), and South Sudan (4.09%).
Interestingly, the fast growing cities are not located in these countries. Instead, the majority of the world’s fastest growing urban populations are mainly found in China and India. These cities are Suzhou, China (5.57%); Guangzhou, China (4.66%); Surat, India (4.4%); Luanda, Angola (4.25%); and Kinshasa, Democratic Republic of the Congo (4.17%).
Future Population Growth Projections
Several organizations have attempted to predict what the world’s future population will look like. The UN Population Division has estimated a population of 9 billion by 2050 and 10 billion by 2100. Many other researchers, however, believe that the population growth pattern might actually be reversed during that time. This is because, in the majority of countries around the world, the fertility rate is actually declining. In some places, it has reached two children per woman, and in other places, it is below that number. The replacement level is considered 2.1, the amount of children needed to sustain the current population size. As previously mentioned, the current global fertility rate is 2.52. If it reaches 2.1, the population will likely remain between 9 and 10 billion.
How Many People Can Earth Support?
All of these predictions about future population growth lead to one very important question: just how many people can the earth support? While the number of people on the earth continues to grow, the size of the planet and its resources do not. At some point, the population may become too much. Overpopulation of any species results in resource scarcity. Several estimates have suggested various carrying capacities for the earth (dependent on resource consumption), ranging from 7.7 billion to 10 billion. Beyond those numbers, and humans could face shortages in food, water, and energy.