The confected frenzy splashed across the morning front pages from the Telegraph to the Mail is remarkable mostly for its absurdity. An outrage machine has decided that a forecast of a few billion pounds in a model that makes projections about trillions of pounds of taxes and spending is the lie of the century. We can’t predict the weather next year, but apparently the public finances in 2029 can be judged with pinpoint accuracy. That’s why the headlines about “holes” and “sleaze probes” are a joke. It is theatre, but it is bad theatre.
The Office for Budget Responsibility (OBR) possesses no great moral or predictive authority. Yet many of its accusers and defenders treat it as an all‑seeing oracle. In fact, the OBR, to its credit, admits that its medium-term projections are frequently wrong. It often wrongly estimates inflation and productivity, and has had its assumptions upended by unforeseen events. The OBR’s 2019 five-year forecast undershot actual GDP growth by £200bn. Given this degree of error, treating a projected current budget balance of £20bn in 2029-30 as a hard fact is deeply unserious.
