Japan August National CPI New Core CPI Unchanged as Deceleration in Food Prices Offsets Impact of Soaring Naphtha and Memor...

Economics Research 18 September 2026 | 9:59AM JST

Japan: August National CPI: New Core CPI Unchanged as Deceleration in Food Prices Offsets Impact of Soaring Naphtha and Memory Chip Prices

BOTTOM LINE: The August national new core CPI (excludes fresh food and energy) Tomohiro Ota | was unchanged from July at +1.9% yoy, coming in slightly below the market forecast Goldman Sachs Japan Co., Ltd. (+2.0%). While the impact of soaring naphtha and memory chip prices led to price increases for some consumable and durable goods, pushing up the new core CPI, albeit slightly, this was offset by a deceleration in food and beverage prices, particularly rice, and some service prices. The global core CPI (excludes food other than alcohol and energy) accelerated by +0.2 pp from July to +1.6% yoy. The core CPI (excludes fresh food) came in at +1.7% yoy, below the market forecast of +1.8%, due to the resumption of government price control measures (electricity and gas).

n National Core CPI (excl. fresh food): yoy, August: +1.7%, GS fcst: +1.8%, BBG consensus: +1.8%, July: +1.8% n National New Core CPI (excl. fresh food and energy): yoy, August: +1.9%, GS fcst: +1.9%, BBG consensus: +2.0%, July: +1.9% n National Global Core CPI (excl. food other than alcohol and energy): yoy, August: +1.6%, July: +1.4% n National Headline CPI: yoy, August: +1.9%, July: +1.9%

Month-on-month (seasonally adjusted)

n National Core CPI: mom, August: +0.1%, July: +0.3% n National New Core CPI: mom, August: +0.3%, July: +0.3% n National Global Core CPI (GS estimation): mom, August: +0.3%, July: +0.3% n National Headline CPI: mom, August: 0.0%, July: +0.4%

The August national new core CPI inflation rate was unchanged from July at +1.9% yoy, coming in slightly below the market forecast (+2.0%). Price increases, likely reflecting the impact of “naphtha-flation”, were seen in some household consumable goods such as detergent and plastic bags, and price hikes, likely reflecting soaring memory chip prices, were seen in some durable goods such as mobile phones and tablet devices, pushing up the new core CPI, albeit slightly (the total positive contribution is estimated to be less than +0.1 pp). Small increases in non-durable goods prices were also seen in items other than those mentioned above. For food and beverage prices, in addition to the continued decline in rice prices, a deceleration was also notable in other items excluding dining-out services, and food

Investors should consider this report as only a single factor in making their investment decision. For Reg AC certification and other important disclosures, see the Disclosure Appendix, or go to

(excluding fresh food) made a negative contribution of just under -0.1 pp.

Private-sector services (excluding rent) decelerated to +0.1% mom annualized (our estimate), from +1.2% in July. While dining-out service prices maintained a solid rise, a slowdown in accommodation charges and mobile phone communication fees were the main negative contributions.

The global core CPI (excludes food other than alcohol and energy) accelerated slightly from July (+1.4%) to +1.6% yoy.

Meanwhile, energy prices decelerated due to the resumption of government price control measures (electricity and gas). As a result, the August core CPI decelerated by -0.1 pp from July to +1.7%, printing slightly below the market forecast of +1.8%.

The headline index was unchanged from July at +1.9% yoy.

The new core CPI inflation rate excluding one-off special factors* (our estimate) accelerated by +0.1 pp from July to +2.3% yoy.

The next announcement of Tokyo CPI data (September) is scheduled for October 2.

Exhibit 1: National CPI indices (year-on-year change) Exhibit 2: National CPI indices (month-on-month change, seasonally adjusted, annualized)

Percent change yoy Percent change yoy Percent change 1m annual rate Percent change 1m annual rate 6 6 10 10 Core (ex freshfood) 5 New core (ex freshfood & energy) 5 8 8 Global core (ex food & energy) 4 Super core (Global core ex rent) 4 6 6

Core (ex freshfood) -6 -2 -2 -8 New core (ex freshfood & energy) -8 Global core (ex food & energy) -

Source: Ministry of Internal Affairs and Communications Source: Ministry of Internal Affairs…