"Between the end of April and early August 2012, the effective exchange rate of the euro depreciated overall amid a renewed increase in volatility," the ECB wrote in its regular monthly bulletin.
"On August 1, the nominal effective exchange rate of the euro, as measured against the currencies of 20 of the euro area's most important trading partners, stood 4.4% below its level at the end of April 2012 and 8.2% below its average level in 2011," the ECB said.
Between April 30 and August 1, the euro lost 6.9% against the US dollar, 9.1% against the Japanese yen and 3.1% against the pound sterling, it said.
Over the same period, the euro fell 2.2% against the Hungarian forint and 1.6% against the Polish zloty. By contrast, it rose 4.2% against the Romanian leu and by 2% versus the Czech koruna, the report said.
"Market volatility increased throughout May from the relatively low levels reached at the end of April but declined during June and has stabilised around historical averages since July," the ECB said.
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