Black Wednesday

In politics and economics, Black Wednesday refers to 16 September 1992, when the British Conservative government was forced to withdraw the pound sterling from the European Exchange Rate Mechanism (ERM) after it was unable to keep the pound above its agreed lower limit in the ERM. In 1997, the UK Treasury estimated the cost of Black Wednesday at £3.4 billion. In 2005, documents released under the Freedom of Information Act revealed that the actual cost may have been slightly less, £3.3 billion. Until the United Kingdom's decision to leave the European Union in June 2016 it was the most significant event to happen during its time as a member of the European Communities (EC)/European Union (EU) and was made even more embarrassing as the United Kingdom was holding the Presidency of the European Communities at the same time.

The trading losses in August and September were estimated at £800 million, but the main loss to taxpayers arose because devaluation could have made them a profit. The papers show that if the government had maintained $24 billion foreign currency reserves and the pound had fallen by the same amount, the UK would have made a £2.4 billion profit on the pound sterling's devaluation.

When the ERM was set up in 1979, the United Kingdom declined to join. This was a controversial decision, as the Chancellor of the Exchequer, Geoffrey Howe, was staunchly pro-European. His successor, Nigel Lawson, a believer in a fixed exchange rate, admired the low inflationary record of West Germany. He attributed it to the strength of the Deutsche Mark and the management of the Bundesbank. Thus, although the UK had not joined the ERM, from early 1987 to March 1988 the Treasury followed a semi-official policy of 'shadowing' the Deutsche Mark. Matters came to a head in a clash between Lawson and Prime Minister Margaret Thatcher's economic adviser Alan Walters, when Walters claimed that the Exchange Rate Mechanism was "half baked".

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