University of Michigan and NBER, United States.
University of Adelaide, Australia.
J Health Econ. 2021 Jan;75:102403. doi: 10.1016/j.jhealeco.2020.102403. Epub 2020 Nov 26.
We examine the effect of an income-based mandate on the demand for private hospital insurance and its dynamics in Australia. The mandate, known as the Medicare Levy Surcharge (MLS), is a levy on taxable income that applies to high-income individuals who choose not to buy private hospital insurance. Our identification strategy exploits changes in MLS liability arising from both year-to-year income fluctuations, and a reform where income thresholds were increased significantly. Using data from the Household, Income and Labour Dynamics in Australia longitudinal survey, we estimate dynamic panel data models that account for persistence in the decision to purchase insurance stemming from unobserved heterogeneity and state dependence. Our results indicate that being subject to the MLS penalty in a given year increases the probability of purchasing private hospital insurance by between 2 to 3 percent in that year. If subject to the penalty permanently, this probability grows further over the following years, reaching 13 percent after a decade. We also find evidence of a marked asymmetric effect of the MLS, where the effect of the penalty is about twice as large for individuals becoming liable compared with those going from being liable to not being liable. Our results further show that the mandate has a larger effect on individuals who are younger.
我们考察了收入型医疗保险强制参保政策对澳大利亚私人医疗保险需求及其动态变化的影响。该政策被称为“医疗保险附加税”（MLS），是对选择不购买私人医疗保险的高收入个人应纳税所得额征收的一种税款。我们的识别策略利用了 MLS 负债因每年收入波动以及收入门槛大幅提高而产生的变化。利用澳大利亚家庭、收入和劳动力动态调查的纵向数据，我们估计了动态面板数据模型，这些模型考虑了源于不可观测异质性和状态依存的购买保险决策的持续性。研究结果表明，在某一年中受到 MLS 罚款的影响会使当年购买私人医疗保险的概率增加 2%至 3%。如果永久受到罚款的影响，那么在接下来的几年中，这一概率会进一步上升，十年后达到 13%。我们还发现了 MLS 存在明显的非对称效应的证据，即与从应纳税变为不应纳税的个人相比，成为应纳税个人的罚款效应大约是前者的两倍。我们的研究结果还表明，该政策对较年轻的个人的影响更大。
