This article obtains elasticity of taxable income (ETI) estimates using data for NZ over the period, 2001–2017, and using the connection between the ETI and excess bunching at income tax thresholds. Results are reported for the top two thresholds in the tax schedule and for various taxpayer types. Adjustments to tax changes are investigated by comparing ETIs obtained from persistent bunching at thresholds when the tax regime is unchanged, with transitory values associated with specific tax reforms. Results suggest substantial bunching around both tax kinks, with ETIs of around 0.2–0.3 across all taxpayers. Evidence suggests large responses by the self-employed, with ETIs of around 0.8–1.0. No significant differences between males and females were found. Adjustment costs and/or inattention biases associated with a shift in a tax threshold were equivalent initially to around 18% (declining to 6%) of the observed excess mass at the post-reform threshold.

中文翻译：

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应税收入和调整成本的弹性：来自新西兰的大量证据

本文使用新西兰 2001 年至 2017 年期间的数据，并使用 ETI 与所得税门槛的超额聚集之间的联系，获得了应税收入弹性 (ETI) 估计值。报告了税表中前两个阈值和各种纳税人类型的结果。通过将在税制不变的情况下在阈值处持续聚集获得的 ETI 与与特定税制改革相关的临时值进行比较，研究对税收变化的调整。结果表明，这两个税收问题都存在大量聚集，所有纳税人的 ETI 约为 0.2-0.3。有证据表明个体经营者的反应很大，ETI 约为 0.8-1.0。未发现男性和女性之间存在显着差异。