1992 in late September, the European foreign exchange market was filled with fierce fighting. On the one hand, the central banks of the member countries of the European monetary system headed by the German central bank are determined to protect the exchange rate of the mark against the pound and the Italian lira, and constantly throw out the mark to buy the pound and the lira in the foreign exchange market. On the other hand, speculative forces in the foreign exchange market seem to be working together against the central bank. In the fierce battle in the foreign exchange market, the central bank has thrown out more than 20 billion dollars of marks, all of which have been eaten by market speculators. In the end, the contest ended in the failure of the European Central Bank to maintain a fixed exchange rate range between the mark and the pound and the lira, and the pound and the lira were forced to withdraw from the European monetary system. Many large venture capital groups earned tens of millions of dollars this month, and the most earned nearly one billion dollars. In fact, the seeds of this crisis in the European monetary system were planted from the day the European monetary system came into being.

1992 12 17 when the fluctuation limit between the currencies of member countries and the exchange rate of the mark exceeds the upper and lower limit, the central bank of the country concerned must intervene. Since the British pound and lira withdrew on September 16, their exchange rate fluctuations with the mark will be determined when they return to the European monetary system.