Editing Special drawing rights (section)

===Currency basket===
To determine the composition of the XDR, the IMF takes into account several currencies important to the world's trading and financial systems. A currency's importance is currently measured by two factors: the amount of exports sold in that currency, and whether that currency is considered "freely usable" (determined by its use as a foreign exchange reserve asset and how widely it is used in international transactions).<ref name=factsheet/>

An XDR basket definition remains valid for five years. Approximately one to two months before the end of this time period, the IMF Executive Board will re-evaluate the XDR basket; the currencies included as well as their weights can then change.<ref name="2011-15weights">{{cite web|title=IMF Determines New Currency Weights for XDR Valuation Basket|url=http://www.imf.org/external/np/sec/pr/2010/pr10434.htm|publisher=IMF|access-date=2015-12-05|date=November 15, 2010}}</ref> Changing the XDR's value definition requires at least 70% of the votes among the IMF members.<ref name="2022weights">{{Cite web |title=Review of the Method of Valuation of the SDR |url=https://www.imf.org/en/Publications/Policy-Papers/Issues/2022/05/16/Review-of-the-Method-of-Valuation-of-the-SDR-517967 |access-date=2022-06-13 |website=IMF |language=en}}</ref> The changes take effect at the end of the five-year period (one to two months after the board review). One business day before taking effect, the newly defined weights are converted to currency amounts based on an average of the exchange rate over the past three months, such that the value of the XDR in U.S. dollars remains the same before and after the change. The currency amounts then remain fixed throughout the five-year period.<ref name="2022weights" />

The IMF reserves the right to perform a re-evaluation after less than five years if it decides that the current basket no longer reflects "the relative importance of currencies in the world’s trading and financial systems";<ref name=factsheet /> it also reserves the right to postpone re-evaluations. If either occurs (causing the old definition to be valid for less or more than five years), the new definition will still be valid for a full five years.