Since the decision on February 12, the Bank gradually and cautiously encouraged the fall in the call rate while carefully monitoring market developments. By April the unsecured overnight call rate had declined to 0.03 percent and has remained stable since then. This call rate of 0.03 percent can be regarded as the de facto zero interest rate taking into consideration transaction fees.
A conspicuous change in the market structure during this period was the downsizing of the call market from 35 trillion yen to 20 trillion yen, or a decline of approximately 40 percent.