ABSTRACT
FOR convenience of exposition we may divide our period into four parts, which I shall call respectively the Breathing Space, the Boom, the Slump and the Doldrums. In assigning dates for these four parts I shall rely on monetary data. Since, however, there are many such data and the various relevant indices do not all move up or down together, dates for the beginning and ending of the Breathing Space, the Boom, the Slump and the Doldrums are not given in nature; if we are to use them, it can only be through the exercise of a more or less arbitrary choice. In some circumstances, of course, the arbitrary element is less than in others, and in all circumstances, the looser the dating, the smaller is the part played by it.
