"Moody's believes that the UK government's decision to leave the EU Single Market and customs union as of 29 March 2019 will be negative for the country's medium-term economic growth prospects. Aside from the direct impact on the UK's credit profile, the loss of economic strength will further exacerbate pressures on fiscal consolidation
Moody's is no longer confident that the UK government will be able to secure a replacement free trade agreement with the EU which substantially mitigates the negative economic impact of Brexit. While the government seeks a "deep and comprehensive free trade agreement" with the EU, even such a best-case scenario would not award the same access to the EU Single Market that the UK currently enjoys. It would likely impose additional costs, raise the regulatory and administrative burden on UK businesses and put at risk the close-knit supply chains that link the UK and the EU. Also, free trade arrangements do not as a standard cover trade in services -- which account for close to 40% of the UK's exports to the EU and 80% of Gross Value Added in the economy -- given the prevalence of non-tariff trade restrictions and the need to align regulations and standards. In Moody's view, the differences of outlook between the UK and the EU suggest that the most likely outcome is now a rather more limited free trade agreement which may exclude services: the UK's desire to pursue its own regulatory policies and to avoid the jurisdiction of the European Court of Justice will make finding an agreement on services challenging. Moreover, any free trade agreement will likely take years to negotiate, prolonging the current uncertainty for businesses."
I fail to understand how anyone can think that it was a good idea to have voted for this act of national self-harm.