their own personal-observation-based information collection and analysis. Diffusion of precision agriculture is thus likely to result in increased employment in agricultural support services, for example, equipment sales, computer software development, customization of equipment and software, and consultant services. The extent to which such increased employment occurs in rural areas depends largely on the combination of direct services and turnkey products through which precision agriculture services are delivered. The greater the extent to which growers purchase precision agriculture services directly, the greater will be the demand for locally based skilled technical labor such as crop consultants and computer software developers and customizers. Any increases in employment in the production of turnkey precision agriculture products are more likely to occur in areas where equipment manufacturers and software developers are currently located, which are largely non-rural.
Increases in rural employment caused by the spread of precision agriculture are likely to be modest. Farm-related employment is presently quite limited. The farm sector as a whole provides an estimated 1.7 million jobs, or 1.3 percent of total U.S. employment (Edmondson et al., 1996). On-farm labor accounts for at least 800,000 of those jobs (National Agricultural Statistics Service, 1996), so that employment in farm services of all kinds is at most 900,000. Precision agriculture is unlikely to generate substantial additional labor demand. Some precision agriculture equipment (i.e., variable-rate applicators) replaces other forms of equipment; neither the manufacture nor the sales of such equipment will require expanded employment. Sales of turnkey products will likely not require increases in sales personnel, although more skilled personnel may be needed to service such products. Software development and customization do not generally require extensive increases in employment.
Above all, the size of the market for precision agriculture products (both equipment and services) in the United States is limited. In 1994, there were an estimated 1.4 million households containing farm operators or managers in the United States (National Agricultural Statistics Service, 1996) and an estimated 2.1 million farm operations (Economic Research Service, 1996). But only a small percentage of those farm operations generate significant demand for farm equipment and services. In 1994, for example, 122,000 farm operations accounted for over 51 percent of total cash expenditures in U.S. agriculture and almost 58 percent of net cash income. An additional 224,000 farm operations accounted for over 22 percent of cash expenditures and 26 percent of net cash income. Thus, a total of 346,000 operations accounted for 74 percent of total farm cash expenses and 84 percent of net cash income, indicating a limited customer base for precision agriculture equipment and services (Economic Research Service, 1996). The sales volume of agricultural equipment like that used in precision agriculture is similarly limited. In 1990, less than 25,000 pieces of crop harvesting equipment and about 50,000 power sprayers and dusters were shipped in the United States. In 1991, farmers spent $604 million on planting and fertilizing machinery, $2,158