RELIABILITY AND ADEQUACY OF FARM-PRICE DATA 
17 
In estimating an annual price for the United States prior to the 
determination of the current year's rate of marketing at the close of 
the year, it would be necessary to use constant weights based on 
marketings until the current marketings are available, unless the 
current marketings are estimated on the basis of market receipts. 
UNWEIGHTED VERSUS WEIGHTED AVERAGES 
The use of an annual United States average price brings up the 
question as to the difference between results obtained by using a 
straight or unweighted average of the United States monthly prices 
and those obtained by using a weighted average. The problem of 
the weighted average resolves itself into a comparison of weights 
based on the usual or average rate of marketing month by month 
and the actual or current rate of marketing in a given year. Table 4 
shows a comparison of the results obtained over a period of years 
in averaging the regular United States monthly prices of wheat and 
of cotton for the year, using constant or usual weights, current 
weights, and no weights. 
Table 4. — A comparison of United States annual farm prices of wheat and 
cotton, unweighted and weighted, oy constant and current year marketings 
[Wheat — cents per bushel. Cotton — cents per pound] 
Crop-year average price of 
cotton 
Crop- year average price of 
wheat 
Crop year beginning— 
Un- 
weighted 
or 
straight 
Constant 
weights i 
Current 
weights 2 
Un- 
weighted 
or 
straight 
Constant 
weights » 
Current 
weights 2 
1908... 
99.9 
101.6 
89.6 
90.9 
82.4 
80.5 
110.3 
99.7 
167.0 
205. 5 
211.1 
227.7 
166.4 
105.6 
100.9 
94.5 
140.0 
95.6 
101.3 
91.3 
88.9 
83.2 
79.5 
102.8 
98.8 
152.2 
206.8 
208.1 
221.6 
181.8 
103.1 
98.7 
93.2 
133.8 
94.8 
1909 
100 7 
1910 
1911 
14.1 
10.2 
11.6 
12.3 
8.0 
11.2 
18.2 
27.8 
28.3 
35.5 
15.4 
16.7 
24.5 
28.6 
23.4 
14.0 
9.7 
11.5 
12.5 
7.4 
11.2 
17.7 
27.2 
28.8 
35.0 
17.2 
16.9 
23.5 
29.0 
23.0 
13.9 
9.6 
11.4 
12.5 
7.4 
11.2 
17.3 
27.1 
28.8 
35.1 
15.9 
17.0 
22.9 
28.8 
22.9 
91.7 
88 3 
1912 
83 3 
1913 
79.3 
1914 
99 4 
1915 
98.2 
1916 
144.4 
1917... 
205 8 
1918 
206 3 
1919 
218.6 
1920 
182.9 
1921 
104.4 
1922 
98.0 
1923 
92.4 
1924 
127.8 
i Constant weights based on usual rate of monthly marketing. 
a The United States monthly prices as regularly determined by method A, weighted by current year 
monthly marketings. 
"When the price of a given product does not change materially 
from month to month throughout the year, that is, when the price 
movement is said to be a horizontal one, it makes little difference 
how the average is weighted, as the results are practically the same. 
In the years 1910, 1912, 1913, and 1915 cotton prices showed little 
change, and the resulting averages are all within 0.1 or 0.2 of a cent 
of each other. A somewhat similar situation existed with wheat 
prices (see Table 4) in the years 1909, 1912, 1913, 1915, and 1917. 
26813°— 27 3 
