经济学人：人口持续减少终将拖累经济

作者：经济学人      来源：一天一篇外刊

If current forecasts are accurate, 2064 will be the first year in centuries when fewer babies are born than people die. Birth rates in India will fall to below the level seen in America last year. Even with immigration and successful pro-natal policies, America’s population will only have a little bit of growth left. By 2100 there will be many fewer migrants left to attract. The world’s fertility rate will hit 1.7. Just two Pacific islands and four African countries will manage to reproduce above replacement level.

如果预言成真，那么2064年将是几个世纪以来第一次“出生人口少于死亡人口”的年份。 届时，印度的生育率将降到低于美国去年的水平。即便有移民流入，再加上鼓励生育的政策取得成效，美国人口也只剩下很小的增长空间。到2100年，世界上可供吸引的移民也会少得多。 届时，全球生育率将降至1.7。全世界只有两个太平洋岛国和四个非洲国家，生育水平还能维持在“世代更替水平”以上。

Sooner or later, therefore, every big economy will collide with a demographic wall. The bill from pensions and hospitals will pile on fiscal pressure. Sapped of workers and ideas, economic growth could collapse while public debt balloons. Just how catastrophic the situation becomes depends on whether policymakers maintain budgetary discipline, withstand pressure from angry older voters and, crucially, are willing to inflict pain on populations now in order to save future generations from more later on.

因此，各大经济体迟早都会撞上人口结构壁垒。养老金与医疗开支不断攀升，财政压力也随之与日俱增。劳动力日渐短缺、创新活力逐步枯竭，经济增长或将陷入停滞，而公共债务却会急剧膨胀。局势最终会恶化到何种地步，关键要看政策制定者能否坚守财政纪律、顶住老年选民的不满压力。尤为重要的是，他们是否愿意让当代民众暂时承受阵痛，从而避免后代在未来付出更为沉重的代价。

America and Europe at least have longer to prepare than East Asia, which is already starting to feel the strain. South Korea has been ageing for a while, but only in the past four years has its population started to decline. It will now continue to fall for decades, as larger generations die off. By 2036 twice as many Koreans will be over the age of 65 as under 18. China will reach a similar point by 2040. America will take until 2100 to catch up.

相较东亚，欧美尚有更充裕的时间应对变局，而东亚如今已然深陷人口压力之中。韩国的老龄化进程由来已久，不过其人口总量直至近四年才开始出现负增长。随着人口基数庞大的世代陆续离世，该国人口在未来数十年里还会持续缩减。到 2036 年，韩国 65 岁以上老年人口数量将达到 18 岁以下青少年人口的两倍。中国也将在2040 年步入同等阶段，美国则要等到 2100 年才会出现这样的人口结构。

The exact size of the demographic hit does not just depend on how quickly populations age, but also on what they expect from the state. In this regard, South Korea has a somewhat bleak advantage. The IMF reckons that its debt-to-GDP ratio, a modest 55%, is unsustainable in the long run and the government is still struggling to get its deficit below a 3% target. Yet few of its elderly were promised state pensions. Instead, nearly 40% of them are in poverty, the highest rate in the OECD club of mostly rich countries.

人口结构变化带来的冲击，不仅决定着老龄化的推进速度，也和民众对公共福利的预期息息相关。 在这一点上，韩国有着一个颇为无奈的 “优势”。国际货币基金组织（IMF）指出，韩国当前债务与国内生产总值之比为 55%，看似处于合理区间，但长期来看难以为继。韩国政府至今仍在努力，力求将财政赤字控制在 3%的目标线以内。 与此同时，韩国绝大多数老年人原本就没有被纳入国家养老金保障体系。如今近四成老年人口深陷贫困，这一占比在由发达国家组成的经合组织（OECD）中位居首位。

The size of the hit will also depend on how economies adapt to a decrepit world. Take government borrowing. Its sustainability reflects the gap between interest rates that prevail when inflation is stable—the so-called neutral rate—and economic growth, which boosts tax receipts. Ageing populations bring gloomy prospects for growth. Research shows that older workers tend to be less mentally agile, and therefore less productive. Shrinking populations could be even worse for growth, which economists believe requires the constant generation of new ideas. Charles Jones of Stanford University has modelled what happens in a world where there are ever fewer people to dream up innovations. The total stock of ideas, he finds, will grow more and more slowly. Economic growth will come to halt; living standards will stall.

冲击程度还取决于各经济体能否适应人口日趋老龄化的大环境。 以政府举债为例：债务能否持续，关键要看中性利率（通胀稳定时期的主流利率）与经济增速之间的差值，而经济增长能够增加财政税收。 人口老龄化会让经济增长前景蒙上阴影。研究表明，年长从业者思维活跃度普遍下降，生产效率也随之走低。人口规模萎缩对经济的冲击则更为严重 —— 经济学家认为，经济增长离不开持续的创新产出。 斯坦福大学的查尔斯・琼斯通过模型推演，分析了创新人才不断减少的社会将走向何方。他得出结论：全社会的创意总量增速会持续放缓，经济增长最终陷入停滞，居民生活水平也将止步不前。

作者：经济学人      来源：一天一篇外刊