Using a new approach relying on news wire reports, we estimate the proportion of secret interventions (i.e., unreported official interventions) in the foreign exchange markets that have been conducted by the three major central banks since 1985. We therefore revisit the estimation of conditional probabilities of secret operations and compute them by both central bank and operation type. The proportion of secret interventions is found to be lower for concerted operations and to display a great deal of variability over time as well as across the three major central banks. Our analysis reveals that the Bank of Japan has recently adopted an intervention policy more based on secret operations.

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