RELIABILITY AND ADEQUACY OF FARM-PRICE DATA 
57 
Table 26. — Percentage difference between December 1 prices and crop-year 
average 1 of monthly prices 
Crop 
Dec. 1 price in excess 
of crop-year aver- 
age price 
Crop-year average 
price in excess of 
Dec. 1 price 
Number 
of years 
Range of 
percentages 
Number 
of years 
Range of 
percentages 
Corn .. 
1 
3 
4 
4 
5 
4.5 
0. 6- 6. 3 
.5-2.3 
. 2- 3. 9 
. 5- 5. 8 
14 
12 
11 
11 
10 
14 
10 
15 
13 
9 
12 
6 
7 
8 
3. 9-26. 7 
Wheat _. 
1. 6-22. 1 
Oats 
1. 1-14. 5 
Barley - . 
1. 3- 9. 9 
Rye 
. 3-14. 5 
Buckwheat 2 .- _. 

4 


6 
. 6-10. 8 
Flaxseed 2 . 
1. 4- 4. 
. 3-15. 2 
1. 9-21. 7 
7. 2-24. 2 
Hay _ 
. 6- 2. 7 
2. 0-25. 4 
Clover seed 3 ------ . .. - - 
1 
1.0-10.8 
9 
6 
5 
1 
4 
. 7-29. 8 
1. 4-25. 1 
. 1- 9. 4 
6.0 
2. 2-12. 8 
. 8-47. 7 
Cottonseed 3 .. --- .. __. - .-. _. . 
. 2-10. 1 
Apples 2 ... -. --. 
1.3-17.0 
Beans .. . .. . .. 
3. 4-20. 8 
Peanuts 34 
1. 1- 8. 3 
Weighted by usual relative monthly marketings. 
1 year, no difference. 
3 Nov. 15 price. 
4 4 years, no difference. 
A comparison of two possible farm-price series as a basis for deter- 
mining the gross value of crop production for the United States 
from 1910 to 1923 is given in Table 27, and a comparison of the 
trend of these two gross values of crop production from 1910 to 
1923 is shown in Figure 14. 
Table 27. — Gr-oss value of United, States crop production 
Value based on December 1 
farm price per unit 
Value based on average of 
monthly prices for season * 
Year 
Gross 
value 
Percent- 
age of 
value of 
preceding 
year 
Index of 
value 2 
Gross 
value 
Percent- 
age of 
value of 
preceding 
year 
Index of 
value 2 
1910- 
Millions 
of dollars 
5,486 
5,562 
5,842 
6.133 
6,112 
6,907 
9,054 
13, 479 
14, 331 
15, 423 
10. 909 
6,934 
8,945 
9,953 
Per cent 
100 
101 
106 
112 
111 
126 
165 
248 
261 
281 
199 
126 
163 
181 
Millions 
of dollars 
6, 211 
6,495 
6,799 
6,717 
7,268 
7,957 
10, 305 
14, 277 
14, 814 
16, 569 
11, 578 
7,759 
9,430 
10, 401 
Per cent 
100 
1911 
101 
105 
105 
100 
113 
131 
149 
106 
1G8 
71 
64 
129 
111 
105 
105 
99 
108 
109 
130 
139 
104 
112 
70 
67 
122 
110 
105 
1912 
109 
1913 
108 
1914 
117 
1915 
128 
1916 
166 
1917 
230 
1918 
239 
1919 
267 
1920 
186 
1921 
125 
1922 
152 
1923 
167 
i Weighted by relative monthly marketings. 
2 Value in 1910 used as 100. 
The correlation between these two trends would necessarily be 
high as the same production figures have been used in each, and 
December 1 prices have tended to move closely wuth average prices 
for the year. The correlation coefficient was plus 0.997 in spite 
of the fact that index numbers (given in Table 27) based on 1910 as 
100, differ by 1 to 9 per cent in various years. During and since the 
war years, the index based on December 1 prices has maintained a 
slightly higher level than the other, because the spread between the 
two gross values was less than in the base period. The correlation 
between the relative change in valuer from year to year is plus 0.979. 
