Tertiary Industry Index MoM

The Indices of Tertiary Industry Activity measure Japan's tertiary production, the output of service industries. METI, the Ministry of Economy, Trade and Industry, compiles this composite index from monthly source statistics, with no survey panel of its own. It covers 13 divisions of the Japanese Standard Industrial Classification (JSIC) regrouped into 10 groups.

It excludes public administration, education-like public activities, manufacturing, construction and farming. Compilation began in 1978 with monthly publication from the March 1999 reference month, and the 2020 base sets the 2019-2020 average at 100.

Each release covers one calendar month, using that month's adopted results with no separate fieldwork, and money series enter in real terms. Each release appears around the 15th of a later month at 13:30 Japan time, about 6 to 8 weeks after the reference month. Dates follow a preannounced schedule that can shift with source-data supply.

Each release brings an overview booklet, charts, time-series files, broad aggregates and reference series. Each release recalculates the prior 3 months, each February-reference release batch-revises all months since January of the prior year, and weights renew every 5 years. Readers watch seasonally adjusted month-on-month change with contributions in percentage points, year-on-year change from the unadjusted original index, a trend sentence and no threshold.

Ten publication groups drive the headline, and larger value-added weights move it more.

• Wholesale and retail trade, 24.1%: goods distribution to firms and to consumers.
• Business-related services and information and communications, 24.5%: professional and technical services, leasing, telecom, broadcasting and information services.
• Medical, health care and welfare, 11.8%: health and care services.
• Real estate, transport and postal activities, and utilities, 22.8%: property, transport, postal and utilities services.
• Finance and insurance, 7.9%: banking, securities and futures dealing, and insurance.
• Living and amusement-related services, 8.9%: accommodation, eating and drinking, personal and leisure services.

The September 2024 data, published November 15, 2024, use the 2015 base, whose average equals 100. The seasonally adjusted index was 102.3, down 0.2% on the month, while the original index was 102.9, up 0.6% on the year. Retail Trade led the fall, down 3.0% with a contribution of minus 0.33 points. Finance and Insurance fell 1.2%, contributing minus 0.13 points, and Wholesale Trade fell 0.6%, contributing minus 0.07 points.

Living and Amusement-related Services rose 1.5%, contributing 0.15 points, and utilities rose 3.4%, contributing 0.13 points. Real Estate rose 1.0% for 0.08 points, Transport and Postal Activities rose 0.4% for 0.04 points, and Business-related Services rose 0.3% for 0.03 points. Broad Personal Services rose 0.2% while broad Business Services held at 0.0%, so a near-flat headline hid sharp splits: read the contributions.

1. Individual index: each industry series is scaled so its base-period average equals 100, after deflating money values with industry-specific price measures.
2. Laspeyres aggregation: the overall original index is a Laspeyres quantity index, a weighted average using base-period value-added weights from the Input-Output Tables totalling 10000.0. Illustrative example: with weights 6000 at 102.0 and 4000 at 98.0, the average is 100.4.
3. Seasonal adjustment: each series is seasonally adjusted with X-12-ARIMA, a statistical method that removes seasonal, trading-day, holiday, leap-year and month-length effects. Adjusted index equals original index divided by the seasonal index.
4. Indirect headline: the headline seasonally adjusted index averages the 10 group adjusted indices with the same weights, rather than adjusting the total directly. The direct adjustment stays on as a reference series.
5. Rates and contributions: month-on-month change comes from the adjusted index and year-on-year change from the original index, with industry contributions in percentage points. Illustrative example: from 100.0 to 100.4 is up 0.4%, and each group's contribution equals its weight share times its own move.