The conventional view is that this is bad news: shrinking numbers hobble economic growth and the ageing population is a major financial burden. But Eberstadt says there is another side. The proportion of Japan’s population that is dependent on those of working age isn’t unusual, he says, it’s just that it has almost twice as many over-65s as children. Consequently Japan spends less on education. And because the Japanese are the world’s healthiest, care bills are also lower than in other nations.

Japan’s economy has been growing slowly for two decades now. But that too is deceptive, says William Cline of the Peterson Institute for International Economics in Washington DC. Thanks to the falling population, individual income has been rising strongly – outperforming most US citizens’.

With 127 million people, Japan is hardly empty. But fewer people in future will mean it has more living space, more arable land per head, and a higher quality of life, says Eberstadt. Its demands on the planet for food and other resources will also lessen.