FERTILIZERS AND AGRICULTURAL LIME 7 



Average Variation from Guaranteed Analysis 



Fourteen firms have registered three or more brands of mixed fertilizers. On 

 the basis of composition found by analysis as well as of tonnage sold, each manu- 

 facturer was successful in maintaining the average plant food guarantees in his 

 mixtures. 



The following table shows that fertilizer manufacturers were more successful 

 in maintaining plant food guarantees in 1946 than in any one of the past ten 

 years. This decided improvement reflects the apparently general practice of the 

 manufacturers to allow a more generous average overrun in formulating their 

 1946 mixtures. 



1937 

 1938 

 1939 

 1940 

 1941 

 1942 

 1943 

 1944 

 1945 

 1946 



Calculation of Shortages 



For calculating the approximate commercial shortages per ton the following 

 figures were used: 



Retail Cost 

 Per Unit 



Nitrogen: 



Water-soluble and synthetic organic $2.00 



Water-insoluble of good quality and 



Water-soluble amounting to one-eighth of the percentage of 

 water-insoluble nitrogen found when the percentage of 

 water-insoluble nitrogen exceeds .50 8.00 



Av; ilable phosphoric acid 1.40 



Potash : 



Muriate - 80 



Sulfate - -- - 1-10 



From cotton hull and boll ashes and wood ashes 1.25 



These values represent the average retail cost to the consumer of the plant 

 food elements in unmixed materials. This does not include mixing and overhead 

 costs which increase the retail cost of these elements in mixed goods. 



To compensate for the increased unit cost in mixed goods the commercial 

 shortage as found by using our values is multiplied by the factor: Actual retail 

 selling price divided by our calculated guaranteed value. 



