Barely more than half of U.S. farm families' income came from farm earnings in 1986, according to an Agriculture Department report.

Jobs in town and other off-farm sources provided the rest. In fact, such earnings generated the bulk of the income for many farm families, according to a coming article in USDA's Farmline magazine.Outside income has represented around half of what farm families earn since 1960, at times surging to as much as 55 percent.

Economist Mary Ahearn of USDA's Economic Research Service says reliance on off-farm income is likely to be greatest on small farms. On the smallest, more than 96 percent of total household income in 1986 came from outside sources.

About two-thirds of U.S. farms are small farms - ones with less than $40,000 in agricultural product sales. They cover about 30 percent of the nation's farmland but take in less than 10 percent of crop and livestock sales.

Less than 4 percent of their net cash income came from farming, according to Economic Research Service statistics. The average in 1986 was about $950 a farm.