Exchequer figures for May show an overall deficit in the public finances of €6.143bn. This compares with a deficit of €63m in the same month last year.
An unexpected increase in the amount of corporation tax collected offset sharp declines across all other tax heads. Spending was up ahead of where it was planned to be by 19% or €4.175bn.
The main areas of extra expenditure were in the Departments of Health as well as Employment Affairs and Social Protection. Corporation tax came in €1.224bn ahead of last year.
The Department of Finance puts this down to increased levels of profitability in some companies and a number of 'one off' factors.