The Bank of Japan shifted the focus of its monetary stimulus Wednesday away from a rigid target for expanding the supply of money, to controlling the shape of yields across different maturities.

BOJ Gov. Haruhiko Kuroda led his board in keeping the benchmark rate for a share of bank reserves at negative 0.1 percent. The central bank said that the monetary base target, which previously had been set at annual increases of ¥80 trillion, may now fluctuate in the short term as policymakers seek to control the yield curve.

The BOJ scrapped a target for the average maturity of its government bond holdings. Board members also pledged to expand the monetary base until inflation is stable above the 2 percent target — committing to an overshoot of consumer-price gains.