WPI (WHOLESALE PRICE INDEX) is wholesale price based index which was used earlier. But CPI (CONSUMER PRICE INDEX) is inflation index based on what in fact customer practices so it is superior index to calculate inflation than WPI.
Unfortunately, it is sometimes a big problem that some indicators of macroeconomic development or description of the functioning of the national economy are not fully standardized internationally. Therefore, the analogical indicators of macroeconomic characteristics of the national economy functioning published by individual countries are not fully comparable. For example, the composition of factors, basket of products and services in the CPI price index are not exactly identical in individual countries.