I thank my noble friend Lord Higgins for reminding me of that question; I was intending to deal with it directly. There is a ready reckoner in the OBR. Our debt is fixed-rate, so the effect of interest rates going up increases over time as debt matures and
as we borrow more. For example, if we had a 1% increase in gilts rates, by 2015-16 that would be costing us just over £4 billion more per annum in debt service costs. That gives a sense of the sensitivity. By 2017-18, it would more or less double to just over £8 billion.