People walk near Gwanghwamun Square in Seoul, Sept. 23. Yonhap

South Korea is projected to see its population drop significantly over the next 50 years, and its global population ranking fall by 30 notches over the ultra-low birth rate and rapid aging, data showed Monday.

The country's population is projected to come to 36 million in 2072, down 30.8 percent from this year's 52 million. Its population peaked in 2020 and has been on a decline, according to the data by Statistics Korea.

The world population, however, is forecast to continue to rise during the cited period to reach 10.22 billion in 2072, compared with an estimated 8.16 billion this year.

South Korea was the world's 29th most populous country in 2024, but the ranking is expected to fall to 59 in the 2072, the agency said.

The country is facing grim demographic challenges as many young people opt to postpone or give up on getting married or having babies in line with changing social norms and lifestyles, as well as amid the tough job market and rising home prices.

The fertility rate, the average number of children a woman bears in her lifetime, came to a fresh low of 0.72 in 2023, down from 0.78 the previous year.

It was much lower than the replacement level of 2.1 that would keep South Korea's population stable at 51 million.

According to the forecast, South Korea's population dependency ratio is projected to grow to 118.5 people in 2072 from this year's 42.5 people, which means much greater pressure on the productive population.

The ratio refers to the percentage of children aged 0-14 and adults aged 65 or older to 100 economically productive people, or those aged 15-64.

South Korea was the world's 208th on the list involving 236 nations in 2024, but it is forecast to take third place in 2072 after Hong Kong and Puerto Rico, according to the data.

Elderly job seekers visit job fair in Yeouido, Seoul, Oct. 26, 2023. Yonhap

The share of people aged 65 or older reached around 19.2 percent of the total population this year and is expected to surge to 47.7 percent in 2072.

The proportion of the working-age population, or those aged 15-64, came to about 70.2 percent of the total in 2024 but will sink to 45.8 percent in 2072.

South Korea is widely expected to become a super-aged society in 2025, in which the proportion of those aged 65 and older will hit 20 percent of the total population.

The country became an aged society in 2017, as the proportion of such people exceeded 14 percent.

North Korea's population is forecast to peak in 2032 before falling to 23 million in 2072 from 26 million in 2024. As a result, the combined population of South and North Korea would come to 59 million in 2072, compared with 78 million in 2024.

India was the most populous country in 2024 with 1.45 billion, followed by China with 1.42 billion and the United States with 345 million.

In 2072, India is forecast to maintain the top position to be followed by China and the U.S. (Yonhap)