研究：世界人口將在2064年達到峯值後開始下降

科學家預測，世界人口將在2064年達到97億的峯值，然後就開始下降，到2100年將降至88億，包括日本、意大利在內的23個國家的人口將減少一半，全球人口結構也將發生重大變化。

The world's population is likely to peak at 9.7 billion in 2064, and then decline to about 8.8 billion by the end of the century, as women get better access to education and contraception, a new study has found.

一項新研究發現，隨着女性有更多機會接受教育和採取避孕措施，世界人口可能會在2064年達到97億的峯值，然後會在本世紀末降到約88億。

By 2100, 183 of 195 countries will not have fertility rates required to maintain the current population, with a projected 2.1 births per woman, researchers from the Institute for Health Metrics and Evaluation at the University of Washington's School of Medicine said.

華盛頓大學醫學院健康指標與評估研究所的研究人員稱，到2100年，195個國家中有183個國家的生育率將不足以維持現有人口，預計平均每位女性生育2.1個孩子。

Some 23 countries -- including Japan, Thailand, Italy, and Spain -- will see populations shrink by more than 50%, researchers said.

研究人員指出，包括日本、泰國、意大利和西班牙在內的23個國家的人口將縮水超50%。

The modeling study, published Tuesday in The Lancet, also forecasts dramatic declines in working-age populations in countries including India and China.

這篇7月14日發表在《柳葉刀》上的模擬研究還預測，印度和中國等國的勞動年齡人口將劇減。

But as fertility declines, researchers note that immigration could offset population shrinkage, particularly in countries with low fertility, such as the US, Australia and Canada.

隨着生育率的下降，研究人員指出，移民可以抵消人口縮水，尤其是在生育率低的美國、澳大利亞和加拿大等國家。

"The world, since the 1960s, has been really focused on the so-called population explosion," Dr Christopher Murray, who led the research, told cnn. "Suddenly, we're now seeing this sort of turning point where it is very clear that we are rapidly transitioning from the issue of too many people to too few."

這項研究的領頭人克里斯多夫·穆雷博士告訴美國有線電視新聞網說：“自從20世紀60年代以來，世界一直在關注所謂的人口大爆炸。突然間，我們發現了這一轉折點，顯然我們正在從人太多的問題迅速過渡到人太少的問題。”

Using data from Global Burden of Disease study 2017, researchers predicted that the fastest-shrinking populations will be in Asia and eastern and central Europe.

運用2017年全球疾病負擔研究的數據，研究人員預測人口減少最快的地方將是亞洲、東歐和中歐。

The report authors project that the population of Japan will shrink from around 128 million people in 2017 to 60 million in 2100, Thailand will see a shrink from 71 to 35 million, Spain from 46 to 23 million, Italy from 61 to 31 million, Portugal from 11 to 5 million, and South Korea from 53 to 27 million.

研究報告的作者們預計，日本人口將從2017年的約1.28億減少到2100年的6000萬，泰國將從7100萬減少到3500萬，西班牙將從4600萬減少到2300萬，意大利將從6100萬減少到3100萬，葡萄牙將從1100萬減少到500萬，韓國將從5300萬減少到2700萬。

Murray said that not only will the population shrink, but society will generally be older, which would have a substantial impact on economic growth.

穆雷稱，不僅人口會縮水，社會年齡結構也會整體老化，這將對經濟增長產生重大影響。

"There's more people needing to receive benefits from the government, whether that's social security or health insurance, and there's fewer people to pay taxes," he explained.

他解釋道：“更多人需要從政府領取福利金，無論是社保金還是醫保金，而納稅的人更少了。”

Researchers project that the population of sub-Saharan Africa could triple over the course of the century, from an estimated 1.03 billion in 2017 to 3.07 billion in 2100.

研究人員預計，撒哈拉以南非洲人口將在本世紀末增至原來的三倍，從2017年的10.3億左右增加到2100年的30.7億。

North Africa and the Middle East is the only other region predicted to have a larger population in 2100 than in 2017, with a predicted 978 million compared to 600 million.

除了撒哈拉以南非洲，預計人口會增加的地區只有北非和中東，該地區的人口預計將從2017年的6億增加到2100年的9.78億。

The study also predicts major changes in the global age structure as fertility falls and life expectancy increases, with an estimated 2.37 billion people over 65 years globally in 2100, compared with 1.7 billion under the age of 20.

這項研究還預測，隨着生育率下降和壽命延長，全球年齡結構將發生重大變化，2100年全球65歲以上人口估計將達到23.7億，而20歲以下人口只有17億。

The global number of people older than 80 could increase sixfold, from 141 million to 866 million. Meanwhile, the number of children under the age of five is forecast to decline by more than 40% -- from 681 million in 2017 to 401 million in 2100.

全球80歲以上人口將增加5倍，從1.41億增至8.66億。與此同時，5歲以下嬰童數量預計將減少40%以上——從2017年的6.81億減少到2100年的4.01億。