While the United States and Canada have some of the most productive farms in the world, France and Norway produce slightly more economic output per person employed in agriculture.
Notes from the World Bank: Agriculture comprises value added from forestry, hunting, and fishing as well as cultivation of crops and livestock production. Data are in constant 2000 U.S. dollars. Agricultural productivity is measured by value added per unit of input. Agricultural value added includes that from forestry and fishing. Thus interpretations of land productivity should be made with caution. Among the difficulties faced by compilers of national accounts is the extent of unreported economic activity in the informal or secondary economy. In developing countries a large share of agricultural output is either not exchanged (because it is consumed within the household) or not exchanged for money. Agricultural production often must be estimated indirectly, using a combination of methods involving estimates of inputs, yields, and area under cultivation. This approach sometimes leads to crude approximations that can differ from the true values over time and across crops for reasons other than climate conditions or farming techniques. Data on employment are drawn from labor force surveys, household surveys, official estimates, censuses and administrative records of social insurance schemes, and establishment surveys when no other information is available. The concept of employment generally refers to people above a certain age who worked, or who held a job, during a reference period. Employment data include both full-time and part-time workers.
Data Source: World Bank, Economic Indicators. Table 3.3. Agriculture value added per worker (constant 2010 US$) (EA.PRD.AGRI.KD). http://wdi.worldbank.org/table/3.3#
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