Japan is officially shrinking. Last October's census found 19,000 fewer Japanese than the previous year; the first time, barring the catastrophic year of 1945, that the population has dropped since censuses began in 1920.
The peak population figure of 127.75 million may well one day be burned into the brains of future students. By 2050, the figure's expected to fall to 100 million and some predictions have the last Japanese switching off the lights sometime in the next century.
Of course, such doomsday scenarios seldom materialise but the shrinking population already has consequences, notably on the country's creaking pension and health systems which face collapse under the strain of an inverted population pyramid.
Other signs of strain are all around, for those looking. Old people died in the heavy snowfalls during winter because their roofs were laden with snow, said the former head of the Tokyo Immigration Bureau Hidenori Sakanaka. 'In the past, young people would have cleared that snow, but there are no youngsters left in the countryside.'
Alarmed at such developments and the stubbornly low fertility rate - which slipped to 1.28 in 2004 - Mr Sakanaka recently poked his head above the bureaucratic barricades to suggest that Japan allow entry to 20 million immigrants over the next 50 years.
Mr Sakanaka was then head of the Tokyo Immigration Bureau; a conscientious civil servant with three decades' experience of controlling the movement of people; not the most promising source for radical solutions to social problems. Yet amid the careful language in his book, Nyukan Senkih (Immigration Battle Diary), there was a startling, even utopian message: Japan must embrace multi-ethnic society and become a magnet for immigrants from all over Asia.