If you’re in a good mood, why not consider ruining it by reading this week’s OBR report. The fiscal watchdog paints a bleak picture of the health of the British economy and the public finances over the rest of this Parliament – one in which the UK is in a steady state of decline, funding a level of public spending that looks increasingly unsustainable. Four of the OBR’s projections lay bare the scale of the challenge ahead. [...]