From the standpoint of production per farm, there has been a tremendous increase every decade. As an average of 1880–1889, the production per farm was 66,420 units, as compared with 67,990 units for the 1890–1899 decade, 71,600 units for the 1900–1909 decade, and 81,000 units for the 1910–1919 decade. In response to the higher price level, the productivity of the average farm has constantly been increasing. If both the general price level and the price of farm crops had been the same in the 1910–1919 decade as in the 1900–1909 decade, the probabilities are that the average production per farm would have been about 73,000 economic crop units instead of 81,000. If by the 1940–1949 decade we have a population of 150,000,000, and if Dun’s index number at that time is $170, it will be necessary to pay at Chicago an average of about $1.80 for wheat, $1.15 for corn, and 65 cents for oats, in order to call forth as much production per capita as was called forth by the prices paid during the past forty years. When Dun’s index number is as low as $170 (at this writing, in early 1920, it is $244), $1.80 for wheat, etc., will be very high relatively. Rather than pay such a high relative price, the consumers of the United States will probably turn to Argentina and other countries where farmers produce food cheaply by living on a lower standard. The position of the United States, rising out of the world war, whereby she is the creditor nation of the world, will favor food importations. It is a commonplace among business men that good crops mean good business. The effect, however, is not as close as they imagine. The short crop of 1901 did not affect the business world till 1903 and 1904. The short crops of 1892, 1893 and 1894 did not have full effect till 1895 and 1896. A single crop year which is only slightly below average may have no effect whatever on business. But when three crop years average below normal, there is almost certain to be some effect on business. From 1903 to 1919, the correlation between crops and the price of securities on the stock exchange was about .53. Professor H. L. Moore, in his book on “Economic Cycles,” finds between crop yields per acre and pig iron production a correlation coefficient of .72, pig iron production lagging about a year behind crops. Big crops do mean good business, altho they mean prosperity to the farming class chiefly in an indirect way. A small crop generally brings farmers more money than a large crop, but small crops over a period of two or three years cause business depression and this reacts on farmers. The problem of both business men and farmers is to devise some means of giving farmers as a class a financial interest in producing big crops rather than small crops. Part II MATHEMATICAL STUDY OF SUPPLY AND DEMAND IN THE HOG MARKET