China this year gave the lie to several myths of the prelapsarian era. Decoupling is bunkum and even turbo-charged engines can lose steam.

By December, conventional wisdom – and Chinese growth data – were exploding fast. Exports fell 2 per cent year-on-year in November, or by 10 per cent if you strip out currency appreciation. Industrial production growth plunged. Deflation is speeding round the corner: the consumer price index has fallen from 8.7 to 2.4 per cent in under 10 months, and factory gate prices increased a thin 2 per cent in the year to November. None of these readings are a blip. With virtually all the developed world in recession – the main end-buyers of Chinese goods – tumbling exports are not going to reverse any time soon. Excess capacity in the manufacturing sector, meantime, suggests deflation could be about more than cheaper food bills.