Something tells you that the government knows this. As Robert Peston points out over at his blog, gilt sales are forecast at £220 billion this year - well above the £180 billion or so that most analysts thought we'd see. The markets will be wondering: just why does the Treasury need to borrow so much now? And the response to that question will have investors trembling.
UPDATE: The Red Book is using trend growth of 2.75 percent for the public finances. But, crucially, even this is exaggerated. HMT independent forecasts have 2.2 percent for 2011; 2.6 percent for 2012; and 2.6 percent for 2013.
UPDATE 2: Scratch the first update. The Treasury is using 3.25 percent growth assumptions for public finances from 2011 onwards. Absolutely unbelievable.