This classification system is based on members' actual, de facto, arrangements as identified by IMF staff, which may differ from their officially announced arrangements. The scheme ranks exchange rate arrangements on the basis of their degree of flexibility and the existence of formal or informal commitments to exchange rate paths. It distinguishes among different forms of exchange rate regimes, in addition to arrangements with no separate legal tender, to help assess the implications of the choice of exchange rate arrangement for the degree of monetary policy independence. The system presents members' exchange rate regimes against alternative monetary policy frameworks with the intention of using both criteria as a way of providing greater transparency in the classification scheme and to illustrate that different exchange rate regimes can be consistent with similar monetary policy frameworks. The following explains the categories.