54 BULLETIN 1480, IT. S. DEPARTMENT OF AGRICULTURE 
Georgia and Texas farm prices of cotton and the New Orleans 
prices for Middling cotton. 
" UTILIZATION OF FARM-PRICE DATA 
No one series of prices is equally suitable for all purposes, but 
for practical reasons it is not feasible to develop a new series of 
prices to fit each new use. Those using the farm-price data of the 
department should, therefore, understand their characteristics and 
realize both their advantages and limitations. For this reason a few 
of the purposes for which the farm prices are used are listed below, 
and some of the more outstanding advantages and disadvantages of 
the series for each purpose are discussed. 
COMPUTATION OF VALUE OF CROP PRODUCTION 
The December 1 prices of crops were developed primarily for 
the purpose of calculating, as of a given date, the value of in- 
dividual crops in the various States. Within each State these prices 
are weighted by acreage, a fairly close measure of relative produc- 
tion within a State, whereas the United States average is weighted 
by production in the several States. The December 1 prices have 
been obtained since 1866 and are used to determine the value of crop 
production as of December 1. These values have been used as a 
basis for comparing the value of the same crop in the different 
States and the values of different crops in the same State and in 
the United States. They have also been used as a means of comparing 
over a period of years values of individual crops and the gross 
value of crop production and for comparing the value per acre 
of different crops and of all crops both in different States and over 
a period of years. 
The series of monthly prices of farm crops, begun in 1908, is 
weighted in the same manner as the December 1 prices, and the 
weighted crop-year average of the monthly prices has also been 
used in computing the value of crop production for the whole United 
States. 
A pertinent question in connection with the use of farm-price data 
in computing the value of crop production is whether the price 
received for the quantity of a product sold is a fair indication of 
the value of the quantities not sold. There is no other very satis- 
factory method of valuing products that are not bought or sold. 
Corn silage, for example, is almost never sold. It may be variously 
valued by different individuals at the cost of production or at what 
it is worth for feed in comparison with the cost of other available 
feeds. Valuations on either of these bases or on any other base are 
difficult to obtain from voluntary correspondents, since the question 
requires them to make an estimate in regard to something they have 
no adequate basis for judging. The department avoids this difficulty 
by assuming that corn put into a silo has the same value per acre 
as corn husked for. grain. This gives a total value which may be 
only approximately correct but which has the advantage of showing 
yearly changes very accurately. 
Not all of the corn crop is of merchantable quality; it varies 
greatly in different years. The farm price of corn is based on the 
