I am informed by the Revenue Commissioners that it is not possible to provide the information sought by the Deputy. The Revenue Commissioners do not require rental income data to be returned in a manner which would enable commercial and private rental accommodation income, reliefs and allowances to be separately identified.
However the Deputy may wish to note that the 2013 Report of the Comptroller and Auditor General contained, in Chapter 16, a detailed review of the taxation of rental income and expenses deductible therefrom. This report is available on the website of the Comptroller and Auditor General and can be accessed via the following link
http://audgen.gov.ie/documents/annualreports/2013/report/en/Chap16.pdf.