AN APPRAISAL OF POWER USED ON FARMS 
69 
^ Table XVIII. — Percentage of total year's farm work done each month, based upon 
* estimates of county crop re-porters, etc. — Continued 
State 
Jan. 
Feb. 
Mar. 
Apr. 
May 
June 
July 
Aug. 
Sept 
Oct. 
Nov. 
Dec. 
New Mexico 
Arizona 
Utah 
Nevada 
Idaho 
Washington 
Oregon 
California 
2.3 
3.5 
1.7 
3.2 
1.2 
2.1 
2.3 
5.3 
3.8 
4.5 
1.6 
4.0 
1.5 
3.3 
4.1 
5.6 
6.7 
4.8 
4.9 
10.0 
5.1 
8.3 
7.5 
7.6 
13.1 
10.7 
10.9 
9.5 
11.1 
11.7 
9.8 
8.2 
12.7 
15.7 
16.4 
8.0 
12.4 
12.0 
9.0 
8.9 
9.3 
14.2 
10.0 
13.0 
11.3 
9.5 
10.5 
11.9 
9.7 
10.8 
12.2 
13.2 
13.0 
10.7 
13.4 
11.7 
11.2 
5.8 
12.4 
11.2 
14.7 
12.5 
13.7 
11.0 
14.6 
11.8 
13.8 
10.8 
13.0 
12.0 
12.9 
10.4 
9.9 
8.7 
8.7 
8.8 
9.4 
10.7 
8.7 
7.8 
3.9 
5.8 
5.0 
4.5 
5.5 
4.6 
5.5 
6.8 
2.8 
3.7 
2.4 
.3.8 
1.8 
2.6 
2.6 
4.8 
United States 
2.8 
3.7 
6.8 
10.4 
12.6 
13.1 
11.3 
8.9 
9.8 
9.9 
7.1 
3.6 
Table XIX. — Approximate average cost per horsepower-hour of animal labor in 
1924^ 
First cost of animal $75. 00 
First cost of harness 30. 00 
Average drawbar horsepower-hours developed annually, 490. 
Annual interest on horse and harness, at 8 per cent 4. 20 
Annual depreciaton due to age, at 5 per cent 5. 25 
Housing, taxes, and insurance per year 10. 00 
Cost of feed and care not chargeable directlv to work, at 16.5 cents per 
day 1 60. 00 
Total fixed charges per j-ear 79. 45 
Credit for manure creditable to fixed charges 8. 45 
Net total fixed charges per year 71. 00 
Depreciation per horsepower-hour chargeable directly to use . 012 
Cost of feed and care per horsepower-hour chargeable directly to use . 067 
Cost of shoeing, veterinary, and harness repair per horsepower-hour . 012 
Total operating cost per horsepower-hour developed . 091 
Less credit for manure chargeable directly to work done . 007 
Net operating cost per horsepower-hour developed . 084 
Net cost per drawbar horsepower-hour and per year, including both operating 
and fixed charges for various amounts of power developed annually 
Horse- 
power- 
hours 
developed 
annually 
per drawbar 
horsepower 
Fixed 
charges per 
horsepower- 
hour 
Operating 
charges per 
horsepower- 
hour 
Total 
cost per 
horsepower- 
hour 
Total cost 
per year per 
drawbar 
horsepower 
100 
200 
300 
400 
500 
600 
700 
800 
1,000 
$0. 710 
.355 
.237 
.177 
.142 
.118 
.101 
.089 
.071 
$0,084 
.084 
.084 
.084 
.084 
.084 
.084 
.084 
.084 
$0,794 
.439 
.321 
.261 
.226 
.202 
.185 
.173 
.155 
$79. 40 
87.80 
96.30 
104.40 
113. 00 
121. 20 
129.50 
138. 40 
155.00 
1 Does not include wages of driver when horses are in use, but does include wages for time required for 
care of horse when not actually at work. Wages for the driver were excluded in these computations because 
they vary indirectly with the size of unit used and also because in some operations much of the attention 
of the operator is devoted to manipulating the machinery used rather than caring for the power unit. 
