428 AGRICULTURAL ECONOMICS 



In making use of the census materials, the original statistics 

 by counties are of first importance. The descriptive material 

 which describes the quality of the statistics is next in impor- 

 tance. The text which is intended to supplement the statistics, 

 while useful, is of less permanent importance then the detailed 

 statistics. 



State census reports, the annual reports, and more recently, 

 the Year Books of the United States Department of Agriculture, 

 and the state agricultural reports contain valuable statistics. 

 Market reports in trade papers and in reports of boards of trade, 

 etc., provide statistics of use in the study of prices. While 

 these various sources are not all that may be desired, the student 

 will find that anything he can do for himself in the collection and 

 tabulation of statistics will be but a drop in the bucket in com- 

 parison with the data available in these sources which have 

 been prepared by the statistician. Since he is so dependent 

 upon these sources of material, it is important that the agricul- 

 tural economist be in close touch with the agricultural statistician 

 who is preparing these source books. 



The use of market statistics may be illustrated by a study of 

 the relation of the price of corn to the supply and price of hogs. 

 The causes of the high prices of hogs on the Chicago market 

 in 1910 can best be understood by studying the history of the 

 hog and corn industries as shown by the market statistics. 

 When the statistics of prices are studied it is an undeniable fact 

 that hog prices were higher in 1910 than they had been at any 

 other time for a long series of years, as shown in Figure 23. 



The general theory being accepted that this rise in price must 

 be due to some change in the conditions of supply or the condi- 

 tions of demand, the student should proceed to study the con- 

 ditions of supply and demand. By charting the supply of hogs 

 on the Chicago market month by month, the fact becomes clear 

 that during the years 1909 and 1910 the supply of hogs was un- 

 usually short. The price of hogs was unusually high during 

 the same period. Little time is required to make the inference. 

 But what was the cause of the shortage of hogs? One may pro- 

 ceed to formulate hypotheses which may be put into the form 



