Key information of new UN population report

A new UN report released on Wednesday updated population estimates with new data from national censuses in 2010 as well as recent health and demographic surveys.

The following is its key contents presented in a Q&A format.

Q: Is it important for us to continuously renew population estimates?

A: Of course. Population estimates play a huge role in figuring out how to slow the danger of global warming and eliminate poverty and hunger.

Understanding the demographic change as well as the challenges and opportunities they present, is key to the design and implementation of new development agenda.

Q: Which are the most populous countries on Earth?

A: China and India remain the two most populous countries in the world with 19 percent of the globe's population living in China and 18 percent in India. India is set to overtake China as the world's largest country in population in less than 10 years, while Nigeria will pass the U.S. to have the world's third-largest population, behind India and China, by 2050 or so.

Currently, the world's 10 largest countries in population are in Africa (Nigeria), Asia (Bangladesh, China, India, Indonesia and Pakistan), Latin America (Brazil and Mexico), Northern America (the United States) and Europe (Russia).

Q: How fast is Earth's population growing?

A: In 2015, the world has around 7.3 billion inhabitants, adding 1 billion people since 2003 and 2 billion since 1990. The world population is expected to reach 8.5 billion by 2030, 9.7 billion in 2050 and 11.2 billion in 2100.

The highest growth rates are in Africa, although fertility rates have fallen there in recent times. High birth rates mean that 41 percent of Africans are aged under 15 and Africa's population is expected to roughly double in size between now and 2050.

Q: Is it alright if our population grows too fast?

A: Of course not. The concentration of population growth in the poorest countries presents a distinct set of challenges, making it more difficult to eradicate poverty and inequality, to combat hunger and malnutrition, and to expand educational enrolment and health systems.

Q: What are the other causes of population change?

A: Another cause of population change is immigration with most migrants moving from low- or middle-income regions with higher fertility to high-income countries. Over the past 15 years, there has been an average annual net flow of 4.1 million such migrants.

Q: Is the fast population growth the only problem for Earth?

A: Not really. For many countries today, and probably for most countries in the long run, the major concern about their demographic situation will be in relation to population aging, not growth.

The number of people aged 60 and above should be more than double by 2050, and Europe will lead the way with more than 34 percent of people there expected to be over 60 years old by 2050. Endi