The global population is predicted to peak in 2064, clocking in at an estimated 9.73 billion, and decline by nearly a billion by 2100, according to a report by the University of Washington.

“Our findings suggest that continued trends in female educational attainment and access to contraception will hasten declines in fertility and slow population growth,” the study reported.

Researchers at the University of Washington’s Institute for Health Metrics and Evaluation plotted trajectories of the total fertility rate (TFR) for the five countries with the largest populations, including the U.S., which is also forecasted to decline.

“A sustained TFR lower than the replacement level in many countries, including China and India, would have economic, social, environmental, and geopolitical consequences,” the report purports. “Policy options to adapt to continued low fertility, while sustaining and enhancing female reproductive health, will be crucial in the years to come.”

By 2100, the United States is expected to have the fourth largest population, trailing India (nearly 1.1 billion), Nigeria (791 million), and China (732 million). The U.S. is forecasted to surpass Pakistan (248 million), rounding out the top five.

“China was forecasted to become the largest economy by 2035 but in the reference scenario, the USA was forecasted to once again become the largest economy in 2098,” according to the report.

U.N. experts predict a 109 million population decline by 2050, triple the 2019 prediction, The Dallas Express reported. Researchers expect the global population to peak at 9.7 billion around 2064 before falling to 8.8 billion by the end of the century, the BBC reported.

Though not one of the top five populations in the world, Japan is currently witnessing a dramatic slowing in birth rates, according to the Statistics Bureau of Japan’s monthly report, and is also aging quickly.

“Japan is standing on the verge of whether we can continue to function as a society,” said Fumio Kishida, Japan’s prime minister, the British Broadcasting Corporation (BBC) reported. “Focusing attention on policies regarding children and child-rearing is an issue that cannot wait and cannot be postponed.”

In Japan, which has a population of 125 million, fewer than 800,000 babies were born last year, according to estimates, down from approximately 1.2 million in the 1970s.

After Monaco, Japan now has the second-highest percentage of people 65 and older in the world (about 28%). Because of the recent increase in life expectancy in Japan, there are now more older adults than there are workers to keep the economy going, making the problem there more acute, the BBC reported.

By the end of the century, researchers predict that Japan’s population will decline from a high of 128 million in 2017 to less than 53 million. Even though Japan has made some changes to its immigration laws, they are still very strict. Some experts now say the laws should be changed even more to help the aging population.

China’s population fell for the first time since 1961, The Dallas Express reported last week. Yi Fuxian, a demographer, said China’s population decline would slow the global economy, reduce revenues, and put the government in debt due to health and welfare costs, Reuters reported.

Yi said the decline in manufacturing and the labor force would worsen U.S. and European inflation and prices. China lost 850,000 people in 2022, the first time since the Great Famine. Kang Yi, head of the national statistics bureau, told reporters that labor supply exceeds demand, despite the decline. In rural areas of China, the imbalance is reducing family formation, The Dallas Express reported.

The Dallas Express reached out to several experts on the topic of Asia and its people, but none of them had responded by the time of publication.