This paper studies a case when the government levies a payroll tax on the employee (agent) of an enterprise. We use a continuous-time principal-agent framework to analyze the impact of the tax on the employee’s working strategy and derive an incentive compensation scheme. The agent is supposed to be aware of his pre-tax and after-tax salary. Under the theory of behavioral economics, loss caused by taxation is taken into consideration. The Hamilton-Jacobi-Bellman (HJB) equation of principal’s profits is derived. By exploiting the HJB equation, we get several properties of the optimal contract. We also perform comparative statics to show our results. The model suggests that the agent’s utility loss enlarges as the tax rate increases. However, an increase in the tax rate does not always decrease principal’s profits.

本文研究了政府对企业雇员（代理人）征收工资税的案例。我们使用连续时间委托代理框架来分析税收对员工工作策略的影响并推导出激励补偿方案。代理人应该知道他的税前和税后工资。在行为经济学理论下，考虑了税收造成的损失。推导出了委托人利润的 Hamilton-Jacobi-Bellman (HJB) 方程。通过利用 HJB 方程，我们得到了最优合约的几个属性。我们还进行了比较静态分析以显示我们的结果。该模型表明，代理人的效用损失随着税率的增加而扩大。然而，税率的提高并不总是会减少委托人的利润。