Earned Income Tax Credits and Labor Supply: New Evidence from a British Natural Experiment, National Tax Journal

With many countries considering the adoption of a system of earned income tax credits, it is useful to analyze how different types of credits affect labor supply and earnings. This paper focuses on a 1999 reform to the UK tax credit system, which increased the value of the credit and reduced the phase-out rate. Using panel data, with individual fixed effects, I compare eligibles and ineligibles within five groups: all individuals; those whose demographic characteristics predict that they will have low earnings; single women; women in couples; and men in couples. Over a 15-month period, boosting the credit appears to have raised the labor participation rates, hours, and earnings of those who were eligible to receive it.

鉴于诸多国家正考虑引入劳动所得税抵免（Earned Income Tax Credits）制度，分析不同类型的抵免如何影响劳动供给与所得收入具有重要的研究价值。本文聚焦英国1999年对税收抵免制度的改革，此次改革提高了抵免额度，并降低了抵免渐退率（phase-out rate）。本文采用纳入个体固定效应（individual fixed effects）的面板数据（panel data），对五类群体中的符合抵免资格者与不符合资格者展开对比：全体个体；人口统计特征预示其收入偏低者；单身女性；有配偶女性；有配偶男性。在15个月的观测周期内，提高抵免额度似乎推动符合抵免资格群体的劳动参与率、工作时长与收入水平实现提升。