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Today in science: The Day of 6 Billion

Global population reached 6 billion in 1999 and 7 billion in 2011. Today – October 12, 2017 – it stands at about 7.6 billion, according to United Nations estimates.

Visitors pack into an artificial wave pool at a resort in Daying county in Sichuan province, China. China Daily/Reuters. View images of World Population Day 2015 from ibtimes.co.uk.

Visitors pack into an artificial wave pool at a resort in Daying county in Sichuan province, China. Image via China Daily/Reuters.

October 12, 1999. The United Nations Population Fund (UNFPA), marked this date as the Day of 6 Billion. That’s because – on October 12, 1999 – the world’s human population was estimated to hit 6 billion, according to the United Nations. It took hundreds of thousands of years for Earth’s human population to reach 1 billion in 1804. The 3 billion milestone came in 1960. Not quite 40 years later, global population had doubled to 6 billion.

In 2011, global population reached 7 billion mark. Today – October 12, 2017 – it stands at nearly 7.6 billion.

Population experts did not agree on the exact date that world population reached the six billion milestone, but they came close. For example, the U.S. Census Bureau set the date just a few months earlier, on July 22, 1999. These numbers are estimates, after all.

Illustration showing estimated world population from 1800 to 2010, using sourced from the United Nations as of the year 2015. Projected population after 2015 are the UN’s three projection types, “low,” “medium,” and “high” population growth. Image via Wikimedia Commons.

Human population is still growing, and, in fact, it’s growing slightly faster than experts a few years ago thought it would. Driven by growth in developing countries, population is now expected to reach 8.6 billion by 2030. It’s expected to reach around 9.8 billion in 2050. These numbers represent a mid-range. Some projections are higher, or lower.

As of 2017, China (with 1.4 billion inhabitants) and India (1.3 billion inhabitants) remain the two most populous countries, comprising 19 and 18% of the total global population. In roughly seven years, or around 2024, the population of India is expected to surpass that of China.

Among the 10 largest countries worldwide, Nigeria is growing the most rapidly. Consequently, the population of Nigeria, currently the world’s 7th largest, is projected to surpass that of the United States and become the third largest country in the world shortly before 2050.

By the year 2100, there should be somewhere around 11.2 billion humans on the Earth.

All of these figures are via a new United Nations report – World Population Prospects: The 2017 Revision – released in June, 2017.

Population growth over time, by region. Data via World Bank. Last updated September 18, 2017. Via Google.

The UNFPA pointed out that the Day of 6 Billion came only 80 days before the year 2000, allowing excellent comparisons to past populations:

In only 40 years, the world population had doubled. In 100 years, it had quadrupled. In only 12 years, it had increased by one billion. Median projections for population growth estimated that by the year 2050, the tally would top 9 billion, with an increase of roughly 77 million people per year.

UNFPA statistics released in September 1999 also stated that the child had a less than 1 in 10 chance of being born into “relative prosperity,” and a 3 in 10 chance of being born into “extreme poverty.”

See real-time human population figures here.

World population percentage by country. Graphic uploaded to Wikimedia Commons in March, 2017. Source: Worldometers.

Bottom line: On October 12, 1999, global human population was estimated to hit 6 billion, according to the United Nations. UNFPA, aka the United Nations Population Fund, marked this date as the Day of 6 Billion.

Read a 2015 statement from UNFPA on 10 things you didn’t know about world population.

Deborah Byrd

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