Data have been collected on the yield of tuna-liver oil since 1940; 

 howeverj for the first few years the figures do not accurately indicate 

 the actual production, since large quantities of wash oil were used in the 

 manufacturing process, which disguised the quantity and value of tuna- 

 liver oil extracted. It is probable that the peak production of tuna- 

 liver oil occurred in 1%5, when the yield was reported as 51s 399 gallons, 

 valued at $1, 576,922 o As a result of the decline in th price of natural 

 vitaaiin oils, production of this oil has declined since that year, and, in 

 1951, totaled only 12,979 gallons, valued at $272, 942 „ It is probable that 

 the production of tuna-liver oil in 1952 was even less than in the previous 

 year. It is estimated that the production of solvibles manufactured from 

 tuna waste in 1952 amounted to about 36 million pounds, valued, at $1,600,000. 

 The total value of tuna by-products produced in 1952 was afcouL $5*000,000. 

 This compares with the figiire of $113,000,833 already mentioned as the value 

 of the 1952 pack of canned tuna and tunalike fishes. With this comparison 

 it is easily discernible that presently the mainstay cf the domestic tuna 

 industry is the sale and consumption of the canned productu of the industry. 



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