https://www.ccomptes.fr/system/files/2022-07/20220707-synthese-RSPFP.pdf
https://taxfoundation.org/flat-tax-state-income-tax-reform/
https://www.brookings.edu/wp-content/uploads/2021/06/financial-stability_report.pdf
https://www.brookings.edu/articles/the-hutchins-center-explains-the-neutral-rate-of-interest/