"Windfall tax receipts" refers to the estimated corporation tax receipts that are not linked to the domestic economy and could, as a result, be transient. All corporation tax receipts, as with all other Exchequer taxes, are paid into the Central Fund. Central Fund revenue is not hypothecated to particular forms of expenditure and, as such, it is not possible to link estimates of windfall receipts to expenditure in the manner requested by the Deputy.
However, in principle, it is certainly true that windfall revenues are not an appropriate basis on which to base day-to-day spending. That is why Government has established the Future Ireland Fund and the Infrastructure, Climate and Nature Fund, to instead set aside a portion of excess tax receipts to prepare for future known challenges.