The yuan rose above 6.4 per dollar for the first time in 17 years, while the dollar fell after the Federal Reserve said this week it will keep interest rates at record low for two more years to revive the flagging US economy. The Chinese currency rose the most since November while 12-month non-deliverable forwards (NDF) increased to a three-month high after the central bank’s daily reference rate rose the most in 2011. The yuan touched 6.3938 earlier, the highest level since China unified official and market exchange rates at the end of 1993. The Chinese central bank set its reference rate 0.27% stronger at 6.3991, the biggest increase since November. The yuan is allowed to trade up to 0.5% on either side of the official rate. The band was last expanded on May 18, 2007, from 0.3%.

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