I am advised by the Revenue Commissioners that the only data available in relation to the taxable income of non-residents comes from income tax returns filed in Ireland by those non-resident individuals who have Irish-source income or income derived from working in Ireland. The available data does not distinguish between citizens and non-citizens.
For the 2007 tax year, the latest year for which data is available, aggregate Irish-taxable income shown on returns filed by non-resident individuals (of all nationalities) amounted to approximately €150 million and the related tax liability amounted to approximately €43 million. Revenue is not in a position to predict with any accuracy the equivalent figures for 2010.