The costs of growing and harvesting farm crops vary widely from farm to farm and year to year. Costs of producing a crop on a particular farm are difficult to determine, especially on farms where several different crops are grown. Yet it is very important that individual farmers keep track of their costs of production as a basis for making better management decisions. Crop production costs per unit vary from farm to farm for many reasons. The most important factor is usually the differences in yield per acre, or more significantly the difference in bushels or cartons sold per acre. Achieving a high rate of sales per acre has to be the result of many factors.