4 Flux, Fall in Prices during the past Twenty Years. 



is weighted in accordance with the , estimated importance 

 of the commodity concerned, that writers of great 

 eminence have considered the process of weighting to 

 be a quite unnecessary complication in the calculations. 



I do not propose to refer you to the course of any 

 of the ordinary weighted averages; but there exists a 

 series of numbers which contain within themselves such 

 a weighted mean as is here referred to. Mr. Stephen 

 Bourne has, in a series of papers, given calculations of 

 the value which our foreign trade in any year would 

 have had if the price of each article entering into it 

 had averaged the same as it averaged in the preceding 

 year. The Economist has for several years published 

 calculations on the same basis, and I propose to utilise 

 these two sets of calculations, which carry us back as 

 far as to a comparison of 1878 with 1877, adding my 

 own calculation of the corresponding figures for one 

 further year. 



There are certain special features connected with the 

 combination of these separate calculations which must be 

 noticed. If every article entering into the trade were 

 entered in the returns, both by quantity and by value (and 

 accurately in both), and if the several different qualities 

 of otherwise similar substances were separately recorded, 

 a very accurate presentation could be made of the varia- 

 tion of the cost of our Imports, or the price obtained for 

 our Exports, which was due to price-changes only, and 

 the average variation of the quantities dealt with might 

 then be deduced. It is not possible, however, to deal 

 thus elaborately with the matter. Some classes of goods 

 cannot conveniently be quantified otherwise than by 

 the misleading means of their weight. To enter lace, 

 umbrellas, millinery, &c, by weight, for example, would 

 not afford a sound basis of comparisons of quantity. In 

 other cases dissimilar articles, the amount of each of 



