Likewise the growing monetary use of gold accentuated strongly the effects, between 1873 and 1883 of a comparatively small decrease in gold production.] Sec.4.

#Index numbers.# The process of calculating general prices and changes in them has in it, inevitably, something of arbitrariness and incompleteness.

For not all prices can be included, but only those of articles of somewhat standardized grades and those that are pretty regularly sold in markets where prices are publicly quoted.

Any list of articles that can be selected is of unequal importance to different persons and classes of persons, at different places, at different times, and for different purposes.

And yet the study of general prices as shown by any broadly selected list reveals changes which in some measure affect the interests of every member of the community.
General prices are conveniently compared from one time to another through the use of index numbers.