FISHERY INDUSTRIES OF THE UNITED STATES, 1935 339 



known fishery products imported or exported have been assembled 

 in one table and published annually in the reports of the Division in 

 recent years. For earlier years they are available in the reports of 

 the Bureau of Foreign and Domestic Commerce, the Bureau of Sta- 

 tistics, the Department of Commerce and Labor, and the Treasury 

 Department. 



PRACTICES AND TERMS 



Certain practices and terms of importance used in the compilation 

 of fishery statistics are explained below. 



Days absent. — In computing "days absent" for vessels landing fares 

 at the various ports, the day of departure and the day of arrival are 

 included; thus, a vessel leaving port on the 8th of the month and 

 returning on the 15th of the month will be shown as being absent 

 8 days. 



Operating units. — Operating units as referred to in this document 

 include persons engaged in the fisheries and fisliing craft and gear 

 employed. 



Vessel. — The term "vessel" refers to a craft having a capacity of 

 5 net tons or more. 



Boat. — The term "boat" refers to a craft having a capacity of less 

 than 5 net tons. 



Incidental catch. — The term "incidental catch" refers to the catch 

 of certain species by a type of gear which ordinarily does not capture 

 such species. 



Percentages. — Percentages are usually shown as whole numbers. 

 Fractions of percents are dropped if less than five-tenths, and the 

 percentage is raised to the next higher integer if the fraction is greater 

 than five-tenths. If the fraction is exactly five-tenths, the integer is 

 raised or lowered to make it an even number. 



Converting. — Many of the figures shown in the statistical tables 

 published herewith have been reduced to thousands of pounds or 

 dollars. In maldng these conversions the largest number from which 

 a group of items is computed is raised or lowered to the nearest 

 thousands place. If the number ends in an even 500, the thousands 

 integer is raised or low^ered to make it an even number. The indi- 

 vidual items are changed to conform to the total thus obtained. 



Confidential data. — The statistical data collected by the Division are 

 confidential and are not released except by approval of the Washington 

 office. Statistics of production of wholesale and manufacturing firms 

 are published only for commodities or geographical areas where the 

 production of three or more concerns may be grouped. Every efl'ort 

 is made to publish only those figures which will rot reveal individual 

 enterprise. 



CONVERSION FACTORS 



It is the policy of the Bureau to show the detailed catch figures of 

 all products in pounds for the sake of uniformity and for purposes of 

 comparison. Following such a policy presents certain problems. In 

 the case of fish there is little difficulty since in very rare instances are 

 such products reported in units of measure other than pounds. For 

 shellfish, however, the units of measure may be bushels, sacks, barrels, 

 or thousands of shellfish, gallons of meats, etc. These many units 

 make standardization difficult, but when coupled with the wide varia- 



