One of the important sources for the increase of human knowledge is the keeping of careful records of a system over time, the study of which may reveal patterns and relationships that otherwise would not be perceived. Despite the existence of more than 60 years of national income statistics and their various components and supplements, such as unemployment and labor force figures, price levels, relative prices, etc, there has been a dismaying lag in the use of this data to detect previously unrecognized relationships among economic variables.

One of the reasons for this disturbing...