The poet William Blake once claimed to “see a world in a grain of sand,” and “eternity in an hour”. The closest Wall Street gets to Blake’s verse is technical analysis, the discipline in which a chart can hold the key to an entire market.

Lately Wall Street has been growing ever more prosaic. Citigroup’s Smith Barney unit in February fired the technical analysis team headed by Louise Yamada, whom Institutional Investor magazine placed at the top of its rankings for four consecutive years.