Critics say my estimate – that the British economy is around 5 per cent smaller due to Brexit – is implausibly large. This insight tests their scepticism against other ways to estimate the cost of Brexit.

The impact on trade overall appears to have been broadly consistent with predictions so far, that on immigration much less negative (and perhaps even positive) and on investment somewhat worse. Perhaps the best estimate of the negative impact on Brexit on UK GDP to date is 2–3% of GDP.