Thirty-two years from now, two out of every three human beings in the world will be living in cities.

That probably, is no longer news.

What is, is that this urban population boom will be concentrated in three countries – Nigeria, India, and China.

According to United Nations estimates released on Wednesday, the world’s rural population will peak in a few years then decline by 2050.

A report on urbanization by the Population Division of the U.N. Department of Economic and Social Affairs (UN DESA), say findings of urbanization advancing so dramatically due to population growth and to migration can help cities design policies and practices to prepare for the influx, said John Wilmoth, director of the Population Division.

“When urban growth is rapid, insuring access to housing, water, sanitation, electricity, public transport, education and health care for all is especially challenging,” Wilmoth said at a U.N. news conference.

Also Read: See What Bill Gates Asked Nigeria To Do To Keep Economy Growing

“Managing urban growth to ensure that it is sustainable has become one of the most important development challenges of the current century,” he said.

Tokyo with 37 million people is the world’s largest city but it is due to be overtaken by Delhi around 2028, the report said.

At about the same time, India is expected to surpass China as the country with the world’s largest total population.

As of today, 55 percent of the world population lives in urban areas, increasing to 68% by 2050, the report said.

By 2050, India, China and Nigeria will account for more than a third of the projected growth in the world’s urban population, the report noted.

But this is not all bad news as Wilmoth noted that “urbanization can be seen as positive”.

“The increasing concentration of people in cities provides a way of more economically providing services,” he said. “We find that urban populations have better access to health care and education.”

The concentration of population also may help minimize humans’ environmental impact on the planet, he said.

“However, the challenge is that in many countries, it’s taking place so rapidly ... and large slum areas have developed that are not maybe achieving the goals of sustainable development the way that we would like.”

Also Watch: 2019: Please Join The Race