The speculation would be necessary to give to efficiency to the market, playing stabilizing paper. However, what if it verifies is that volatileness enters the main taxes of exchange surpasses very in the differences in the economic policies of the industrialized countries. The same author observes that the Central bankings had had that to increase its international reserves to be able to intervine in still bigger scale in the exchange markets. This factor not if must in such a way to the exchange regimen, but to the great growth of the flows of capital with the globalization of the markets. Leiderman and Bufman (1995), comparing fixed and flexible the regimen of taxes, stand out that flexibility allows an adjustment macroeconomic faster efficient e. In the practical one, regimes exchange of the different countries has been a variant between free flexibility and permanently fixed taxes.
Simonsen and Cysne (1995) call these limited fluctuations dirty fluctuation, in which the Central banking intervines, sporadical, to brighten up the speculative oscillations of the exchange taxes. The practical problem consists of knowing until point the fluctuations are or not speculative shunting lines in relation to a trend. Other systems had entered in vigor, as the managed flexibility, for which a tax does not exist that the authorities are obliged to defend, even so they intervines to the will; the adjustable setting, by means of which the authorities accept a commitment to defend the tax in the level settled in the period, however with right to modify it in certain circumstances; the mini devaluations, where the tax is fixed, modifying it gradually in the time, by means of a series of small changes, end to brighten up the abrupt variations in the exchange tax; the system of exchange bands, where the fixed Central banking two extreme taxes (inferior limit and superior limit) inside of which it leaves to float the exchange tax freely.