Contemporaries could not be blamed for the failure to foresee the unprecedented length and severity of the Great Depression triggered by the stock market crash of November 1929. The depression of the 1870s was ancient history and could be attributed to the malfunctioning of an immature economy. The older men in public life could recall the year 1893, when business activity was at a peak in January and fell steadily to its lowest point in June 1894, when the recovery that then began was complete by December 1895. Unemployment had not become serious until the depression had run for seven months and began to pick up four to five months later. In 1907 there had been a peak in January, the trough was reached in June 1908, but recovery took business activity to a new peak in January 1910. Industrial unemployment was severe only in the twelve months beginning in October 1907. The depression of 1920–1, though sharp, had been even shorter.

Drawing upon this experience, a reasonably pessimistic analyst in the spring of 1930 might have predicted a severe depression touching bottom in the spring or early summer of 1931 and ending early in 1932. Was the pattern likely to be distorted by the unprecedented losses sustained in the Wall Street crash? “Blood letting” was a phrase much on the lips of those whose business it was to know; unwise speculation and the erection of towering financial structures on insecure foundations were blamed; the losses were supposed to have left untouched the underlying strength of the economy.