Keynes himself asserted in its main book, the Theory of employment, interest and money (1936) that “most investors and professional speculators care less about making precise previsions in the long term than forecasting just before the public the upcoming changes on the conventional evaluation scale”. This approach follows initial Dow’s analysis, the creator of the eponymous index and of the Wall Street Journal. Dow’s theory is a core aspect of technical analysis and is worth developing.