Brexit, trade and echoes of the past
Brexit supporters have been severely critical of the OBR for its grim outlook for the UK post Brexit. The OBR is by no means the most negative of the professional forecasting bodies, and historically its forecasts have tended to err on the side of optimism, as Duncan Weldon observes . But it struggles to find anything good to say about post-Brexit Britain. In particular, it is distinctly negative about the future for Britain's external trade. Brexit is above all a shock to trade, since its primary impact will be on Britain's trading relationships, not only with the EU but with other countries too. At present, we have no real idea what these will look like once the UK has left the EU. The OBR is therefore forecasting under extreme uncertainty. If there is one thing we can be sure of when forecasting under extreme uncertainty, it is that the forecasts are even more likely than usual to be wrong. This does not indicate that the forecasters are biased. It just means they have