Producer price index
A Producer Price Index (PPI) measures the average changes in prices received by domestic producers for their output. It is one of several price indices.
Its importance is being undermined by the steady decline in manufactured goods as a share of spending.
Related measures 
A number of countries that now report a Producer Price Index previously reported a Wholesale Price Index.
PPIs around the world 
United States 
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.”
See also 
- The Economist, Volume 387, May 31 - June 6 2009, page 109
- BLS Handbook of Methods, Chapter 14 Producer Prices, Background (found online at:http://www.bls.gov/opub/hom/homch14_a.htm)
- Senate Committee on Finance, Wholesale Prices, Wages, and Transportation, Senate Report No. 1394, “The Aldrich Report,” Part I, 52nd Congress, 2d sess., March 3, 1893; and U.S. Department of Labor, Course of Wholesale Prices, 1890–1901, Bulletin No. 39, March 1902, pp. 205–09. (found online at:http://www.bls.gov/ppi/ppicpippi.htm)