ng.

This practice, however, is not altogether satisfactory. Firstly, the
concept of a representative budget is necessarily more or less
artificial; the budgets of wage earners, even in the same class, vary
considerably in composition. Thus hardly any figure on the change of the
cost of living has been given out without being challenged by one or
other of the interested parties. Secondly, for all except the lowest
grades of wage earners, the direction of expenditure changes somewhat as
particular prices change in a different measure. This second
disadvantage was noted particularly during the war, when the supplies of
certain commodities were limited or rationed. Thirdly, and this
difficulty is of a more serious nature, the prices of some or many of
the articles which occupy an important place in all calculations of the
cost of living of the wage earners may change in a different measure, or
even in a different direction, from the prices of the other commodities
produced within the country. Food prices in particular are apt to
respond to different influences than those governing the general price
level.[61] However, it is only from the course of change of the price
level representing _all_ important commodities produced within the
country that it is possible to get an indication of the change in the
total conglomeration of market values, which has been called the
product of industry. Even then the indication is far from an exact one.

Let us consider the two cases in which the change in the prices of some
or many articles important in the wage earners' budget diverges
considerably from the change in the index number of the prices of all
important commodities produced within the country. The first case is
that in which the prices of the relatively small collection increase
much faster than the index of general prices. Such might be the fact in
the event of two bad harvests in succession. If wages are increased in
accordance with the movement of the prices of the relatively limited
collection of commodities, the result of the wage increase may be an
increase in prices in general. As a result of this the wage earners may
be better or worse off than before, depending upon circumstances. The
second case is that in which the prices of the relatively small
collection of articles may increase less than the index of prices in
general. In this case any wage increase undertaken in accordance with
the change of prices of the relati