A producer price index (PPI) is a price index that measures the average changes in prices received by domestic producers for their output.[clarification needed]
Its importance[clarification needed] is being undermined by the steady decline in manufactured goods as a share of spending.
A number of countries that now report a producer price index previously reported a wholesale price index.
In the US, the PPI was known as the Wholesale Price Index, or WPI, up to 1978. The PPI is one of the oldest continuous systems of statistical data published by the Bureau of Labor Statistics, as well as one of the oldest economic time series compiled by the Federal Government. The origins of the index can be found in an 1891 U.S. Senate resolution authorizing the Senate Committee on Finance to investigate the effects of the tariff laws "upon the imports and exports, the growth, development, production, and prices of agricultural and manufactured articles at home and abroad".