The Tokyo Retail Price Index began with the Tokyo Retail Market-Price Survey, first prepared in 1904 as internal data for use by the Bank of Japan. This study was intended primarily to ascertain overall changes in the level of prices charged by retailers in Tokyo at the product-sale stage. In January 1922, the BOJ began releasing this data as the Tokyo Retail Price Index. The BOJ continued preparing and releasing the Tokyo Retail Price Index through April 1968.
Tokyo Retail Price Index on July 1914 Base
This index, based on July 1914 figures, was first announced in January 1922 in response to price fluctuations following the First World War. In addition to indexes of prices of 100 individual items, commodity group indexes and an average index for all items are calculated using a simple arithmetic average.
Data sources are the Tokyo Retail Market-Price Survey and the Tokyo Retail Price Index Record, both of which are stored in Bank of Japan Archives.