Number crunching premium bonds | Brief letters

Tax proves taxing | A canal-boating break | Directionless sprinting | Changes that work | How very GuardianThe suggestion that the UK could raise significant sums by increasing the limit on premium bonds is not, unfortunately, mathematically sound (Letters, 17 September). If the money was moved from UK banks and building societies, then it would be moving from a taxed environment to an untaxed environment. So, in addition to paying 3.6% interest in prizes, the exchequer would lose between 20% an