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Q&A about the Consumer Price Index
[A. About the consumer price index (CPI)]
A-2 Since when has the CPI been calculated?
A-3 What is the the index reference period? And what is the weight reference period?
A-5 What indices do they use for measuring underlying inflation?
[B. Calculation of the CPI]
B-1 How do you calculate the CPI?
B-2 Is the CPI calculation method of Japan as same as that of major countries?
[C.Uses of the results]
[D. Revisions to the bases]
D-3 At the base revision of the CPI, how do you link old indices and new indices?
D-5 How much impact did the 2020-base revision have on year-on-year percent changes?
[E. Midpoint-year review]
[F. Quality adjustment]
F-1 What is quality adjustment with CPI for, and how do you make it?
[G. Frequently asked questions about the CPI]
G-2 Are private brand commodities surveyed?
G-3 Are discount stores included as survey subjects?
G-4 Will the CPI appropriately reflect the change of quality such as functional improvement of products?
G-5 It is said that there is an upward bias in Japan's CPI. Is this true?
[H. Consumer Price Index calculated by Laspeyres' chain index method]
H-2 How is the chain index calculated?
H-4 Why do you position the chain index as a supplementary index?
[I. Consumer Tax]
[Others]