在剛剛過去的這一年，令人提心吊膽的經濟新聞層出不窮。而日本最近的困境可能是最令人寒心的警世故事。這個全球第三大經濟體的GDP在2015年第三季度萎縮了0.8%，這也是日本最近7年來第五次在第三季度出現經濟衰退。

盡管日本首相安倍晉三付出了巨大的努力，試圖讓國家擺脫通貨緊縮和負增長的困擾，但效果平平。他的提振經濟計劃包括投入數十億美元進行大規模刺激，推行結構性勞動力改革，松動銀根，但結果卻不盡人意。其中，部分原因在于政治壓力不斷升級，但真正的原因卻更加深層：作為全球老齡化最嚴重的人口，日本的人口數量正在萎縮。

這個島國的人口在過去十年內下降了0.6%，而65歲以上的人口卻增加了20.4%，如今占總人口的比例超過四分之一。面對著未來商品市場的萎縮，日本公司沒有意愿進行資本投資。盡管政府的介入使得日本失業率維持在較低的水準，但人們的實際工資卻沒有實質性增長，所以日本消費者也沒有增加開銷的理由。

In a year with no shortage of scary economic stories, Japan’s recent woes may be the globe’s most chilling cautionary tale. The world’s third-largest economy shrank by 0.8% in the third quarter of 2015, sending the country into its fifth recession in seven years in November.

That’s despite the herculean efforts of Prime Minister Shinzo Abe to rescue the country from the grip of disinflation and negative growth. His plan to jump-start the economy—a multibillion-dollar combination of massive stimulus, structural labor reforms, and monetary easing—has fallen flat, partly because of escalating political pressure. But the real reason goes deeper: Japan’s population, the world’s oldest, is shrinking.

The archipelago’s population has fallen 0.6% in the past decade, while the share of the population older than 65 has risen from 20.4% to more than a quarter. The result is that Japanese companies, facing the prospect of a smaller market for goods, see little reason to invest in new capital spending. And although government intervention has kept unemployment low, real wage growth has been stagnant, giving Japanese consumers little reason to increase their spending either.

不過，與其他國家相比，日本在短期內還不會更差。到2050年，美國、中國和德國等大型經濟體的人口中也會有22%超過65歲，這會對經濟增長和公共資金支持的社會保障體系產生重大影響。日本的債務占GDP比例為全球最高，不過迫在眉睫的債務也可能導致其他國家的這項比例飆漲。

高頻經濟公司首席經濟學家卡爾?維恩伯格表示：“對我們來說這是一種新的經歷?！备挥械膰疫^去一直把整體經濟的增長看作理所當然。他說，而日本，“則是一次現實的檢驗?！?/p>

要緩解這個問題，政府能做的事情很有限。日本的量化寬松項目（比美國的規模要大很多）由日本銀行每月購買80萬億日元的政府債務。以這樣的購買速度，到2027年，中央銀行就會擁有日本全部的政府債務，不過，在此之前，這種貨幣就會崩潰。

全球能避免類似于當下在日本醞釀的財政風暴嗎？我們可以從日本移民這個不同的角度來考慮。盡管日本政界的恐慌情緒越來越嚴重，但年輕的移民可以幫助抵消生育率衰退和人口老齡化帶來的影響。畢竟，所有的刺激措施都無法讓日本的人口增長。維恩伯格表示：“日本需要的不是償債能力，它需要的是人口?！保ㄘ敻恢形木W）

譯者：嚴匡正

審校：任文科

Compared with the rest of the world, though, Japan may not be worse so much as early. Large economies, such as those in the U.S., China, and Germany, are all projected to have 22% of their population over age 65 by 2050, which has vast implications for economic growth and publicly funded social safety nets. Japan’s debt-to-GDP ratio is the highest in the world, but looming obligations could cause others to balloon as well.

“This is a new experience for us,” says Carl Weinberg, chief economist with High Frequency Economics. The rich world has historically taken its collective steady economic growth for granted. Japan, he says, “is a reality check.”

There’s a limit to how much the government can do to alleviate the problem. Japan’s quantitative-easing program (far larger in scale than equivalent efforts in the U.S.) has the Bank of Japan buying 80 trillion yen’s worth of government debt each month. At that rate of purchase, the central bank would own every last dollar of Japanese government debt by the year 2027, though the currency would collapse before that happened.

How can the world avoid a fiscal storm similar to the one now brewing in Japan? It can start by thinking differently from the Japanese on immigration. Despite the panic they increasingly evoke in political circles, younger immigrants can help offset declining birthrates and an aging population. All the stimulus in the world can’t make Japan’s population grow. “Japan doesn’t need liquidity,” Weinberg says. “It needs people.”