This paper builds a new microdatabase that covers 100 countries at all income levels and long-run time series in the United States (1870–2010) and Mexico (1960–2010) to document how the modern tax system arises over development. I establish a new set of stylized facts, which show that the income tax exemption threshold decreases in the income distribution as a country develops, tracking growth in the employee share of employment that occurs gradually further down the income distribution. Additional evidence supports the interpretation that the rise in third-party covered income through increases in employee share drives expansions of the income tax base over development.
Jensen, Anders. "Employment Structure and the Rise of the Modern Tax System." American Economic Review 112.1 (January 2022): 213-234.