New Estimates suggest the Minister for Finance may have about £200 million, and possibly much more, to spend on measures to resolve the Budget tax row - without interfering with his existing arithmetic.
The additional money, which could be used to provide additional tax allowances or direct payments to single-income families, is the result of a probable underestimate of this year's tax revenue, which underpinned the Budgetary calculations.
The underestimate means significant, unexpected money will flow into the Department of Finance this month. The scale of the excess will not be clear until Monday, January 3rd. However, it is certain substantial sums are involved.
Underestimating the 1999 figures means the estimates for 2000, on which the Budget figures are based, are also at too low a level and the overshoot of next year's tax target would be of about the same magnitude.
According to Dr Dan McLaughlin, chief economist at ABN Amro, the Minister for Finance could have up to £350 million to spend on additional measures to defuse the current Budget row.
"The tax receipts are likely to exceed the Government's 1999 estimate by about £350 million to £400 million, which could readily be used to fund a tax package for married women without compromising next year's budgetary figures," he said.
At present, the Government's figures assume that £1.19 billion will flow into the coffers in December. That is only a rise of 2.5 per cent on last year. In November, for example, tax revenues rose by some 15 per cent and that was accelerating from October.
If the rise stayed at the same rate there would be almost £160 million extra and if it accelerated to 16 per cent, it would be closer to £190 million.
The child benefit rises which have already been included in the Budget cost £105 million and so could be doubled or even tripled without changing the overall Budget arithmetic. The Budget raised child benefit by £8 a month for the first two children and £10 a month for subsequent children.
To introduce the £2,000 stay-at-home allowance for married women with children, outlined in the Fianna Fail manifesto prior to the last election, would cost £76 million.
However, last night Mr McCreevy was standing firm. He said the stay-at-home allowance would be tackled, but in another Budget. "We will not neglect our election pledges but it will be done over the lifetime of this Government," he said.
Last year, the Department also underestimated the tax revenue figures and the additional money was used to repay part of the State's debt.