The use of changes in short-term interest rates (STIRs) within a 30-minute window around monetary policy announcements has been increasingly adopted in empirical studies. However, variations of STIRs within such a narrow window may be too small under the effective lower bound (ELB). To address the issue, this paper constructs a measure of monetary policy shocks using STIR futures in Japan, where the policy interest rate has been close to the ELB for an exceptionally long period. We show that (i) variations within a 30-minute window are closely correlated with key financial variables while those outside the window are correlated less, suffering from noise, (ii) expansionary shocks with respect to unconventional measures have continued to lower the long-term yield, and (iii) the impulses of macroeconomic variables to the shocks agree with what conventional theory predicts overall.
Keywords: Monetary policy shocks; high frequency identification; effective lower bound
Views expressed in the paper are those of the authors and do not necessarily reflect those of the Bank of Japan or Institute for Monetary and Economic Studies.