The Subnational Government Structure and Finance Dashboard displays comparable graphs on the institutional organisation and public finance at subnational government level for 38 OECD member countries. The graphs show the averages – weighted – for unitary and federal countries as well as the average for the European Union and the OECD for the latest year available.
This section includes graphs on tax revenue as a percentage of total public tax revenue. You may find the full dataset here: Subnational government tax revenue.
The data is also available in PDF format.