Up until 1970s that central bank communication was based on secrecy and market surprise1. But central banks moved away from surprising markets and, instead, moved to open and transparent monetary policy making. Guidance on the future course of monetary policy was even common practice in some central banks before the crisis.
For example, since 1997, the Reserve Bank of New Zealand has included in its communication practice the release of the numerical projection of the future path of the policy rate. However, forward guidance as it was introduced during this crisis has been an unprecedented step for many central banks; both in terms of scope as well as clarity.