The Charity Commission has not made any assessment of this kind as it is the responsibility of the HMRC to assess the effect of Gift Aid tax relief. HMRC has published research on levels of charitable giving, “Individuals’ Donations to Charities and their Use of Tax Relief.”
A copy of the research reports can be found on the HMRC website at www.hmrc.gov.uk/research/rep9-main.pdf. Copies will be made available in the Library for the reference of Members.