The international monetary fund adopts the exchange rate parity system, which stipulates that all member countries must set the parity of their own currencies. Article 4 of the IMF stipulates that the parity of member currencies is generally expressed as gold 1 ounce (British ounce) equal to $35. The fluctuation of foreign exchange transaction prices in various countries shall not exceed the parity of 1%. After the establishment of the 197 1 Smithsonian agreement, the fluctuation range of this spot exchange rate was expanded to 2.25% above and below the parity, and the standard for determining "parity" was changed from gold to special drawing rights.

As for the parity published by the Fund, it shall not be changed without the consent of the Fund. However, if the balance of payments of member countries is basically unbalanced, the IMF can be asked to adjust the parity. If the whole range is within 10% of the parity, member countries can adjust it by themselves, and the IMF will approve it. If it exceeds 10%, it must be approved by the fund before it can be adjusted.

This parity system is "adjustable pegged exchange rate". Although it is quite close to the gold exchange standard system, the parity of the fund is determined by the fund and the member countries, while the gold exchange standard system is determined by the proportion of gold content.