Britain's financial industry could lose up to 38 billion pounds in revenue in a so-called 'hard Brexit' that would leave it with restricted access to the European Union's single market, according to a report commissioned by an industry group.If finance firms lose the right to freely sell their services across Europe, 75,000 jobs may disappear and the government may lose up to 10 billion pounds in tax revenue, the report by consultancy firm Oliver Wyman said.