Michael McGrath (Cork South Central, Fianna Fail) | Oireachtas source

It is important to look at what exactly Mr. Coffey said in his report in mid-2017, namely that “although it is impossible to be definitive, and the volatility in receipts will remain, the level-shift increase in Corporation Tax receipts seen in 2015 can be expected to be sustainable over the medium term to 2020.”

In 2015 we collected €6.9 billion in corporation tax receipts, an increase of over €2 billion on the previous year. Since then, the figure has risen to €10.4 billion, therefore receipts have increased by 50% since 2015. Last year we collected 22% more than anticipated, which was nearly €2 billion more than we expected. Receipts were €2.2 billion or 27% more than the previous year. The scale of increase since 2015 is quite spectacular. There must be caveats on any assessment - there will be assumptions, it is difficult to forecast this revenue stream - but there is now a key risk for the public finances in making permanent expenditure commitments on the back of what could prove to be a transitory, volatile and temporary tax receipt.

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