22 BULLETIN 910, IT. S. DEPAKTMEXT OE AGEICULTUKE. 
The average of the estimates of these 553 men is 3.820 miles, but 
53 per cent of the estimates were 3,250 miles or less. 
The amount of material hauled from and to the farm, which 
depends on the type of farming and the size of the farm: the size of 
load, which depends on the size of the truck; and the length of haul, 
all have an influence on the distance per year which a truck travels, 
but for the farms under consideration these factors are all corelated 
in such a way that no one of them exerts a predominating influence. 
For instance, the average of the estimates of the number of miles per 
year traveled by the trucks on the farms of different types is as 
follows : 
Miles. 
108 truck farms 3, S00 
93 dairy farms 3, 960 
89 fruit farms 3, 980 
36 crop farms 3, 240 
227 general farms 3, 800 
Similarly, the size of the truck and the distance from the farm to 
market show very little relation to the number of miles traveled per 
year. The average of the estimates of — 
113 men who own ^-ton trucks is 3,790 miles per year. 
80 men who own f-ton trucks is 4.370 miles per year. 
232 men who own 1-ton trucks is 3,660 miles per year. 
52 men who own 14; - and 14- ton trucks is 3,100 miles per year. 
60 men who own 2-ton trucks is 4.070 miles per year. 
16 men who own 2Vton and larger trucks is 4,980 miles per year. 
These farmers were also asked for their estimate of the number of 
days per year on which they used their trucks — not* the number of 
full days work per year which the truck did, but simply the number 
of days on which some use was made of it. The average of the 
estimates of the number of days per year on which some use is made 
of the trucks on farms of different types is shown in Table XIII. 
The dairy farmers use their trucks on the most days and the crop 
farmers on the fewest. The estimates also showed that in general the 
smaller trucks were used on a somewhat greater number of days than 
were the larger ones. 
Table XIII. — Days per year on which trucks are used. 
Number 
Type of farming. cf esti- 
mates. 
Days per 
year on 
which 
track 
is used. 
Track 133 
160 
Dairv 109 
244 
Fruit 99 
159 
Crop 43 
127 
162 
All 639 173 
