But Hong Liang, Goldman Sachs China economist, calculates the PBoC is losing about $4bn a month on its bills because of the turnround in the interest rate differential over the past 18 months.

• 为保持币值稳定，中国央行几乎买下所有流入中国的外汇，然后再通过发行人民币票据来抽走相应流动性，以“冲销”其货币影响。