14 BULLETIN 501, U. S. DEPARTMENT OF AGRICULTURE. 
preciation per cow for each year was determined by dividing the total 
for the herd by the average number of cows. 
On the Wisconsin farm there was no charge for depreciation, and 
only a small charge on the Michigan farm. The average value per 
cow increased from year to year in both of these herds during the 
record period. . Grade cows were sold while still valuable for dairy 
purposes, and their places were filled by pure-bred heifers of home 
raising. The highest depreciation charge, $5.13 per cow, is on the 
Pennsylvania farm, and, considering the average valuation per cow, 
this is a small charge. It is probable that, owing to the herd manage- 
ment, the charge for depreciation is lower on each of these farms 
than may be expected for a period of years on most dairy farms. 
MISCELLANEOUS ITEMS. 
There are a number of minor expenses in connection with the 
maintenance of every dairy herd, and for convenience these may be 
grouped under the heading of " miscellaneous items." These include 
veterinary services, fees to cow-testing association, registration fees, 
ice, and other dairy supplies. The total of these varies on each of 
the four farms, ranging from 66 cents to $2.93 per cow, which is from 
one-half of 1 per cent to nearly 3 per cent of the total cost. 
OVERHEAD. 
There are a number of items of expense in the operation of a farm 
business that can not be charged directly to the individual enterprises.. 
Important in this group are expenses for the general upkeep of the 
appearance of the farm, interest on money borrowed for general 
working capital, farm share of telephone rental, postage, and sta- 
tionery. The importance of this item may be expected to vary 
greatly with the efficiency of management of the farm business. 
On these farms the overhead expenses were distributed to the pro- 
ductive enterprises on the basis of total cost for labor and materials. 
The dairy being the most important enterprise, it is made to carry 
its proportionate share. Overhead on these four farms varies from 
$4.84 to $7.64 per cow, and is 5 to 6 per cent of the total cost. 
CREDITS OTHER THAN MILE. 
There are certain credits apart from milk and milk products, such 
as value of manure, calf, and in some cases an appreciation in value 
of cows, which must be considered in determining the net cost of 
milk. While these credits affect the net cost of milk, they in no way 
change the proportion of any of the factors entering into the gross 
cost per cow; because, were the credits subtracted from each factor 
rather than from the total, the amount subtracted would be pro- 
rated to each item on the percentage basis. The total credits other 
