Before revision:  The currencies include the Australian dollar, Canadian dollar, Swiss franc, euro, British pound sterling, Japanese yen, New Zealand dollar and US dollar . Dominant multiscale cross--correlations between the exchange rates are found to typically occur on the level of small and medium size fluctuations.
After revision:  The study is motivated by fundamental questions in complex systems' response to significant environmental changes and by potential applications in investment strategies, including detecting triangular arbitrage opportunities . Dominant multiscale cross--correlations between the exchange rates are found to typically occur on the level of small and medium size fluctuations.