A new index released by the bank of Japan on Friday shows that Japanese consumer prices rose 1.2 per cent in the year to October after stripping away the effect of energy and fresh food costs.
The BoJ has been using the government's core CPI, which excludes fresh food but includes energy costs, as its key price measurement in guiding monetary policy.
That index, however, fell 0.1 per cent in the year to October, data released earlier on Friday showed.
BoJ thought of revising the CPI after core CPI slipping due largely to slumping oil prices. The new index, worked out internally, shows inflation exceeding 1 per cent in the past few months.
The new index strips away volatile fresh food and energy costs, but includes processed and imported food prices, which are rising.
The BoJ has said it would release the index each month on the day the government publishes its price data.