https://taxfoundation.org/flat-tax-state-income-tax-reform/
https://zoe-institut.de/wp-content/uploads/2021/06/ZOE_Report_A-future-fit-recovery_FINAL.pdf
https://data.oecd.org/natincome/net-lending-borrowing-by-sector.htm
https://www.technologyreview.com/2024/01/25/1087027/climate-subsidies-inflation-reduction-act-mining-critical-minerals/