4 BULLETIN 705, U. S. DEPARTMENT OF AGRICULTURE. 



Crop index. — The yielding power of the soil of a given farm or 

 group of farms expressed as a percentage of the average yielding 

 power of the soil of all farms in the community.^ 



Animal unit. — A mature horse or cow, or as many smaller animals 

 as require the feed of a horse or cow, namely, 2 head of young cattle, 

 2 colts, 5 hogs, 10 pigs, 7 sheep, 14 lambs, 7 goats, 14 kids, or 100 hens- 



Productive animal unit. — Includes all animal units except work 

 horses. 



Receipts. — The gross income of the farms from all sources. 



Expenses. — The total amount necessary to conduct the farm busi- 

 ness during the year. It includes, besides all cash outlay, deprecia- 

 tion of equipment and buildings and all unpaid family labor (excepting 

 that of the operator) used in conducting the farm business. 



Farm income. — The difference between the gross receipts and the 

 expenses. It is the amount available to the farm family for living, 

 saving, and paying debts after the expenses of conducting the farm 

 business during the year have been paid. It does not include what 

 the farm furnished directly toward the family living. 



Percentage farm income is of capital invested.- — Farm income does 

 not include the amount the farm furnishes the family in the way of 

 food, fuel, and the use of the farm dwelling. Neither do the expenses 

 include the value of the operator's labor and the cost of his board. 

 These two amounts, that is, what the farm furnished the family and the 

 value of the operator's labor and the cost of his board, were so nearly 

 equal on the farms studied that percentage farm income is of capital 

 invested is used in this discussion to measure the efficiency of farming. 



1 The crop index may be defined as tlie crop yields of a particular farm expressed in percentage of the 

 average crop yields of all the farms in the community. It is foimd as in the following example: 

 A particular farm produces — 



2, 000 bushels of com on 40 acres, 

 1, 200 bushels of wheat on 40 acres, 

 900 bushels of oats on 30 acres, and 

 120 tons of hay on 80 acres. 



Total 190 



The average yields of the above crops in the community are: Com, 60 bushels; wheat, 32 bushels; oats, 

 40 bushels; and hay, IJ tons per acre. Hence, on the average, the areas required to produce the above 

 quantities of the products mentioned are — 



2, 000-4-60= 33. 3 acres of com, 

 1, 200h-32= 37. 5 acres of wheat, 

 900-7-40= 22. 5 acres of oats, and 

 120h-1|= 68. 6 acres of hay. 



Total=161.9 

 Thus, it requires 190 acres on the farm in question to produce what 161.9 acres produces on the average. 

 Hence, 1 acre produces on this farm 161.9-5-190, or 85.3 per cent as much as the average acre of the com- 

 munity. 



