This allows data to be compared with other SIC code based measurements such as productivity, employment, wages and earnings. Until 1978 known as Wholesale Price Index, one of the oldest economic time series. Originated in 1891 Senate resolution to investigate effects of tariff laws. Has been revised several times. Several other classification systems used.
Most indexes are national in scope.
Regional data available for a few items. Wall Street Journal a. chart on front page and article day after release date b. index and percent change by stage of processing 5.