Will the chancellor manage again to use his Treasury black arts to keep within his economic rules, or will he now have to admit that his forecasts were optimistic? The forthcoming Pre-Budget Report should offer some clues, says Robert Chote.

Gordon Brown has unveiled three big tax-raising Budgets since becoming chancellor eight years ago, each of them in the 12-month honeymoon period following one of Labour's election victories. Is history about to repeat itself in the wake of the party's latest win at the polls in May? Brown's Pre-Budget Report, expected within weeks, should give us a hint.