COST OF USING POWER ON WHEAT FARMS IN OREGON 37 
The cost per 10-hour day of use was considerably higher for large 
combines than for those of the smaller sizes, but the data as given 
in Table 37 shows that there was no significant difference in the cost 
er acre of using large and small sized combines. 
In Table 35 an estimate is given of the 1923 and 1924 average 
cost of operating the combines found on these farms. The cost of 
fuel, oils, and grease is based on an average of the quantities used 
for the three-year period 1920-1922, charged at the prices which pre- 
vailed in 1923 and 1924. (See page 34.) The average amount of 
time spent by the owner and other labor in repair work on these 
machines over the period 1920 to 1922 was charged at the prices 
which prevailed for such labor in 1923 and 1924. The cash repairs, 
insurance, depreciation, and interest charges are the same as those 
that were used for the year 1922. 
The cost per 10-hour day of use in 1923 and 1924 is based on the 
average of the days used over the period 1920 to 1922, inclusive. 
TABLE 35.—Estimated cost of using combines in 1923 and 1924 (Averages for 
combines of all sizes) 
Cost 
Quan- 
Item tity 
1923 | 1924 
Fuel and oil: Dollars | Dollars 
AS LAG een es ee ee gallons_ 484 99 114 
SS ra BG a a re ra ee ee eer Ose 21 4 4 
ONE WT a (0 YT) eee Se SS ees a eee eee dos = 31 26 | 26 
CONF AVES LO 8 (Saas I aa ae ne eS a eee ies eee eae doz== 20 3 3 
ERAT BE CASE a a a eee nae pounds__ 39 4 4 
Repairs: 
CNS) ep Se a a ee peg 193 193 
Ov ehS 1 ADO at ena ae ee ee 2 See eS en eens days_- 7 32 31 
DG EVE Te) ea Yaa ee eR re ee ee Nin One 6 34 33 
WARE ye Soe s mee Ss es ae eh ee ee eee ae ere Pan eee ae 31 31 
BE) © PEC CLAW 0 Ya ete ea re ne ee ures Nn ee a Ses eS 392 392 
BRE Ech eee creer he racy Me ele eee as eR oa ees Te le a 818 831 
ETRE O TOS esas ge ee ee ered tie eae eee nr, ue ew ee ete Sees ale ES 98 98 
PAOLA COS GPT CO TET I LEN Ceca eae a eee Ste sae 916 | 929 
Cost per 10-hour day of use (23.7 days per year)_-_-----_--_------------___|_________- 38. 65 | 39. 20 
EFFECT OF DAYS OF WORK AND ACRES CUT ON COST PER DAY AND PER ACRE 
OF USING COMBINES 
_ The influence of the amount of work done on the cost of operating 
combines is shown in Table 36. The combines were grouped accord- 
ing to the number of days they were used annually, each group 
having its proportionate number of large and small sizes. The 
amount of work done increased with an increase in the days of 
annual use which resulted in lowered costs per acre of grain har- 
vested. ‘These combines were used an average of 23.7 days per year. 
The range in days of annual use was from 7.8 to 39.6. : 
