The Producer Price Index (PPI) is the official measure of producer prices in the economy of the United States. It measures average changes in prices received by domestic producers for their output. The PPI was known as the Wholesale Price Index, or WPI, up to 1978. It is published by the Bureau of Labor Statistics and is one of the oldest economic time series compiled by the Federal government of the United States.
The origins of the index were 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".