But Mr Broadbent pulls together some striking evidence in support, including this wild and wacky chart (below) which looks like an electrical experiment gone wrong, but actually shows the movement of output across 81 sectors of the economy since the late 1990s.

BBC: The UK productivity puzzle (cont'd)

In January 1803 the anatomist and electrical showman Giovanni Aldini shocked London with a ghoulish experiment.

WSJ: Book Review: The Lady and Her Monsters