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Outline of Corporate Services Price Index (CSPI, 2000 base)


April 2009
Bank of Japan
Research and Statistics Department

1. Purpose and uses

The CSPI focuses on the prices of services traded among companies. The CSPI can be regarded as a counterpart of the CGPI, which focuses on the prices of goods traded among companies. The main purpose of the index is to investigate price developments that reflect most sensitively the supply and demand conditions in the services market, with a view to facilitating analyses of macro-economic conditions. The indexes of less-aggregated levels (e.g., Item) also have a "deflator" function that transforms nominal output values into real quantities. In addition, those price indexes can be used as reference indexes in the actual transactions.

2. Classification and weights

The CSPI covers domestic and imported services provided for companies,*1 and excludes services provided for individuals.*2 The index series produced for the basic categories of the CSPI (the Basic grouping index) cover only transactions for domestic and imported services. Transactions contracted in foreign currencies are converted into yen and included in the aggregate. They are also compiled and released in their original currencies as the Reference indexes in the Basic grouping index. The CSPI includes "Export Corporate Services Price Index" and "Corporate Services Price Index excluding Consumption Tax" as the Reference indexes to supplement the Basic grouping index. The weights of the index are based on the transaction values of services during the base year 2000 within the total intermediate sectors of the "Input-Output Tables (I-O Tables)," published by the Ministry of Internal Affairs and Communications. The CSPI is classified into 8 Major groups and further classified into 17 Groups.

  1. *1Services for which it is difficult to conduct reliable continuous price surveys and whose weights should not be imputed to other services selected in the index because of the absence of similar services in terms of characteristics or price developments are excluded (e.g., financial services <imputed interest>, wholesale and retail trade, education and research, public administration).
  2. *2Services mainly provided for individuals but also including those for companies are adopted as surveyed services in the CSPI (e.g., telephone calls, postal services).

3. Base year for the index and the weight calculation

The base year is 2000 for both the index calculation and the weight calculation.

4. Selection of Items

First, services in Basic sectors of the "I-O Tables" whose transaction values of total intermediate sectors are no less than 500 billion yen (about 0.4 percent of the "transaction values of the index" during the base year 2000), are selected as Subgroups. Second, individual Items of each Subgroup are selected on the condition that the value data for calculating index weights are available and that adequate sample prices can be collected continuously. The CSPI covers a total of 110 Items.

5. Sample prices

In principle, sample prices are surveyed at the time of contract primarily based on the following two points: 1) actual prices most sensitively reflecting the supply and demand conditions of the service transactions should be chosen as sample prices; and 2) price developments of surveyed services need to be as genuine as possible. They should be free from price changes caused by changes in the services' quality or contract conditions. The number of sample prices is 3,050 (as of October 29, 2004).
When sample prices are contracted in foreign currencies, they are converted to a yen basis for compiling the yen-basis index using monthly average spot exchange rates (middle rates*3) as quoted by banks to customers in each corresponding month.*4 For details, refer to the column, Sample prices for the CGPI.

The CSPI includes the consumption tax.

  1. *3Middle rates are adopted from the January 2005 figures. Before then, foreign currency buying rates for domestic and exported services and selling rates for imported services were used as exchange rates.
  2. *4Indexes of contract currency basis are also released in "Reference index" for Items including sample prices contracted in foreign currency (Ocean liner, Ocean tramper, Ocean tanker, Oceangoing ship chartering services, International air freight) and for aggregated groupings including those Items.

6. Index formula

The index formula is the fix-weighted Laspeyres formula. For details, see Index formula for the CGPI.

7. Publication

In principle, the preliminary figures are released on the eighteenth working day of the following month after the surveyed month of the index. The release date will be shifted a few working days earlier, when the number of working days in the month is small. The final figures are released two months after the surveyed month of the index, based on revisions to the preliminary figures. Periodic retroactive revisions of published indexes are implemented twice a year in April and October, when the preliminary figures of March and September indexes are released. The published indexes are revised for the past 18 months in principle. Apart from these periodic retroactive revisions, the CSPI will be revised immediately if large errors (such as one resulting in changes at the index level of All items) are found in the published indexes.