I should acknowledge immediately that to state the choice as one of “fixed versus floating” is to oversimplify. Both types of regime are actually broad categories, each of which contains a number of variants.
Fixed exchange rates are almost never irrevocably fixed, for example: Crawling pegs allow the rate to be adjusted in a controlled manner, while some putatively fixed rates are actually re-set at frequent  2  BIS Review 59/2004  intervals, either as an instrument of policy or under external pressure.