But this week Pedro Malan, the finance minister, insisted there would be no change in Brazil's exchange-rate regime.

ECONOMIST: Brazil: The real thing | The

It would indeed be ironic if a change in China's exchange-rate policy came not as a result of American pressure, but from China's own disillusion with the dollar as an international reserve currency.

ECONOMIST: Economics focus

In Argentina , all the main candidates bidding to succeed President Carlos Menem in October's presidential election ruled out any change in the country's fixed exchange rate.

ECONOMIST: Wanted

But governments have also learnt, in a second big change, that intermediate exchange-rate regimes do not work either.

ECONOMIST: One world, one money

Economists reckon that in the 1990s only about half of an exchange-rate change had worked its way through to manufacturing import prices after a year.

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As speculation as to the timing of the change grew markets pushed the exchange rate up 0.4% above the target in early trading, to its highest level since 1994.

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