Operating cost items, except those for farm raised inputs, were taken directly from survey responses to questions about the dairy expenditures for each item. Homegrown harvested and grazed feed costs were computed using market prices for each feed item to estimate the opportunity cost of feed fed to dairy cattle. State average market prices were used to value the harvested feed items fed to dairy cows on conventional dairies (USDA, National Agricultural Statistics Service). Because organic feed prices are significantly higher than those for conventional feeds, premiums paid by organic producers for feed items were estimated.
