Although two organizations have lately succeeded in constructing price indexes which for recent years move in advance of general prices and of basic industrial production,2 the price indexes thus far currently published are not designed primarily as forecasting devices. Price changes are of such interest that indexes are used extensively to tell us what present conditions are, and how they compare with past conditions, quite apart from any consideration of their significance as forecasters. Indeed, a major part of the interest in forecasting arises from a desire to predict the course of prices.
Under these conditions it is not surprising that a wide variety of price indexes are maintained. In the following pages we offer a summary description and comparison of the indexes which are best known and most widely used.3____________________