This paper studies the impact of inflation on income taxes in Sweden, the UK, and the United States during the world wars. As tax reforms were rising top marginal rates and reducing exemption thresholds, extraordinary levels of inflation eroded the real value of exemptions, brackets, and deductions. The micro-simulation of actual and alternative scenarios shows that inflation made the tax less progressive, particularly in Sweden during World War I and the UK during World War II. Nevertheless, its redistributive effect increased due to the related growth in tax revenue. Inflation contributed to transform a “class tax’’ into a “mass tax”.

中文翻译：

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世界大战期间的所得税累进性和通货膨胀

本文研究了二战期间通货膨胀对瑞典、英国和美国所得税的影响。由于税收改革提高了最高边际税率并降低了免税门槛，异常水平的通货膨胀侵蚀了免税、括号和扣除的实际价值。实际和替代情景的微观模拟表明，通货膨胀使税收的累进性降低，特别是在第一次世界大战期间的瑞典和二战期间的英国。然而，由于税收收入的相关增长，其再分配效应增加。通货膨胀有助于将“阶级税”转变为“群众税”。