By Chris Dorrell Leading City figures have called on the Chancellor to scrap the stamp duty on buying shares in a bid to boost London’s capital markets and support growth. With concerns growing about the City of London’s competitiveness and the UK’s sluggish economic performance, new research suggests that abolishing the levy in the Spring Budget could increase long-run GDP by somewhere between 0.2 per cent and 0.7 per cent. The research, commissioned by the Centre for Policy Studies (CPS) and undertaken by independent consultancy Oxera, found that scrapping the tax could increase the overall …