The data release has had negligible yen impact but posting it for those interested (its also at our Economic Calendar). From the calendar:
The Monetary Base released by the Bank of Japan is the "Currency Supplied by the BoJ" including all the JPY in circulation, encompassing notes and coins as well as money held in bank accounts. It is considered as an important indicator of inflation, as monetary expansion adds pressure to the exchange rates. An acceleration of monetary base is considered as positive for the JPY, whereas a decline is seen as negative.
Note those final two sentences are a quick explanation of the economic theory behind monitoring the base figures.