Analysis of an unannounced foreign exchange regime change

► Oligopolistic commercial banks can determine market outcomes. ► The econometric evidence shows a concentration measure is negatively related to exchange rate volatility. ► A theoretical model shows the connection between an oligopolistic FX market and exchange rate dynamics. Starting in 2004 the Guyanese foreign exchange rate has been remarkably stable relative to earlier periods. This paper explores the reasons for the stability of the rate. First, the degree of concentration in the foreign exchange market has increased, thus making the task of moral suasion relatively straightforward once this policy tool comes to bear on the dominant trader(s). Second, long-term or non-volatile capital inflows make the exchange rate less susceptible to sudden reversal. Third, commercial banks, the dominant foreign exchange traders, have large outlays of assets in domestic currency, thus their desire for exchange rate stability. The econometric exercise is consistent with the notion that trader market power has contributed to lower volatility in the G$/US exchange rate. The paper also presents a model that analyzes monetary policy effects in the presence of a mark-up or threshold interest rate.