444 AGRICULTURAL ECONOMICS 



but in spite of that the mean of these four years is o . 3 per cent above 

 that of the ten years 1896-1905, which decade exceeded each of the 

 three preceding decades in production per acre. For the United 

 States the gain was 3.8 per cent over the mean of 1886-1895. 



Potato production per acre in the United States declined sharply 

 from 1866-1875 to 1886-1895, after which there was a marked increase 

 in both the periods following. The gain for the United States was 

 15.3 per cent and the mean of the final four-year period is 15.5 per 

 cent higher than that of the preceding ten years. 



Hay stood higher in mean production per acre in 1896-1905 than 

 in any of the preceding three decades, gaining 22 per cent over the 

 period 1886-1895. A similar sort of statement applies to oats, the 

 gain being 15.6 per cent in the decade 1896-1905. Again, for barley 

 and rye a similar history appears. The former showed n . i per cent 

 and the latter 21.3 per cent increase in the third ten-year period. 

 After thirty years of decadence, buckwheat reached the highest pro- 

 duction per acre in the records of this Bureau. 



The chart on p. 445 shows the fluctuations in yield from 

 year to year and the trend of production of our ten leading 

 crops. 



The statistical test that the farmers of this country have met in 

 the foregoing examination of production per acre is not as severe as 

 the one which in varying degrees and in varying numbers of states 

 they are prepared to meet in a comparison of production per acre with 

 population. There is a prevalent misunderstanding with regard to 

 the nature of the increase of population in this country. It seems to 

 be assumed that the net immigration is to continue for a century and 

 over at the rate of one-half to three-fourths of a million people 

 annually. How quickly immigration can be reduced to zero was 

 shown by the industrial depression of 1908. No one who would take 

 a far sight into the future would reckon upon an indefinite continuance 

 of a considerable immigration. Likewise, the birth-rate of this coun- 

 try, as of all the countries of Western and Central Europe, is a dimin- 

 ishing one; so that while the increase of population must be admitted 

 to the reckoning, a diminishing rate of increase must be recognized. 

 The conclusion of a recent investigator of this problem was that the 

 increase of population in this country, after eliminating the influence 

 of the foreign-born upon the conglomerate national birth-rate, was 

 about i? per cent for the census year, or about 12^ per cent for a 

 decade. 



