Such far-reaching ex ante transparency is, however, due to fail because of the uncertainty from which policymakers suffer just like any other market players. As the cornerstone of policy implementation, the interest rate path needs to be revised constantly and optimised conforming to updated information. When we fixed a target range for the first time in December 1999 we simply did not know that as soon as the first quarter of 2000 two interest rate increases would be necessary. The commitment to ex ante transparency must take account of the knowledge and the uncertainty of decisionmakers. Thus, as a rule, it is hardly meaningful to give information with regard to any other planned interest rate moves in addition to the announcement of the current interest rate target. In so doing, the central bank would lose essential room for manoeuvre, immobilise its internal decision-making process and give rise to counterproductive changes in market expectations. For this reason, I am also sceptical with respect to the somewhat softer practice of preparing the markets with a so-called bias statement for a probable interest rate move. Such signals cause expectations to be revised, which is of small avail in the best case, and ties the central bank’s hands, in the worst case. Once a concrete decision - eg to raise the 5  BIS Review 35/2000  interest rate - has been taken, it can be implemented without delay, ie without a prior announcement.
; Milton Friedman and Anna J. Schwartz (1963), A Monetary History of the United  States, 1867–1960, Princeton University Press; and Ben Bernanke (2004), Essays on the Great Depression, Princeton University Press. 4 Robert L. Hetzel (2008), The Monetary Policy of the Federal Reserve: A History, Cambridge University Press. 5 Milton Friedman (1963), Inflation: Causes and Consequences, Asian Publishing House. 6 Willem Buiter (2016), “Dysfunctional Central Banking; The End of Independent Central Banks or a Return to  ‘Narrow Central Banking’ – or Both?”, Global Economics View, Citi Research, 21 December; Otmar Issing (2016), “Central Banks – From Overburdening to Decline?”, SAFE White Paper Series, No 42. 7 Jakob de Haan and Sylvester C.W. Eijffinger (2017), “Central bank independence under threat?”, CEPR Policy  Insight, No 87. 8 Transparency International EU (2017), Two sides of the same coin – Independence and accountability of the  European Central Bank, transparency.eu/wp-content/uploads/2017/03/TI-EU_ECB_Report_DIGITAL.pdf. 6/6  BIS central bankers' speeches