In Working Documents you can find the document called "Taxation in the OECD: 1965-2018", which describes the methodology of a data base of mean tax rates on consumption, capital and employment for twenty-one countries of the OECD in the 1965-2018 period. These are suitable tax rates for analysing the macroeconomic effects of tax policies. A spreadsheet format provides the data base that is included in the appendix of the aforementioned document.