The latest figures show that China is putting paid to the simplistic story that a cheaper currency on its own boosts exports. Don’t be fooled. The performance of the Chinese economy over the past year is a demonstration of the truth of that. Since Aug. 11, 2015, when the People’s Bank of China, the central bank, abruptly depreciated the renminbi by 1.9 percent, the currency has fallen significantly against those of its major trading rivals. As of last Friday, Aug. 5, it had fallen by 8.6 percent against the US dollar, 10 percent against the euro and by an amazing 31 percent against the Japanese yen.