U.S. Department of Agriculture
访问日期： 16 十月, 2018
Improving agricultural productivity has been the world's primary means of assuring that the needs of a growing population don't outstrip the ability of humanity to supply food. Over the past 50 years, productivity growth in agriculture has allowed food to become more abundant and cheaper (see Growth in Global Agricultural Productivity: An Update, Amber Waves, November 2013, and New Evidence Points to Robust But Uneven Productivity Growth in Global Agriculture, Amber Waves, September 2012). A broad concept of agricultural productivity is total factor productivity (TFP). TFP takes into account all of the land, labor, capital, and material resources employed in farm production and compares them with the total amount of crop and livestock output. If total output is growing faster than total inputs, we call this an improvement in total factor productivity ("factor" = input). TFP differs from measures like crop yield per acre or agricultural value-added per worker because it takes into account a broader set of inputs used in production. TFP encompasses the average productivity of all of these inputs employed in the production of all crop and livestock commodities. "Growth accounting" provides a practicable way of measuring changes in agricultural TFP across a broad set of countries and regions, and for the world as a whole, given limited international data on production outputs, inputs, and their economic values. The approach (described in detail in Documentation and Methods) gives agricultural TFP growth rates, but not TFP levels, across the countries and regions of the world in a consistent, comparable way. Most of the data for the analysis comes from FAOSTAT. In some cases Food and Agriculture Organization (FAO) input and output data are supplemented with data from national statistical sources. Note: To facilitate international comparisons, certain simplifying assumptions must be made, and as such the estimates of TFP growth reported here may not be exactly the same as TFP growth estimates reported in other studies using different assumptions or methods. In particular, our TFP estimates for the United States differ slightly from those reported in ERS' Agricultural Productivity in the U.S. data product.