Taxes and the Timing of Births
利用美国青年纵向调查数据，发现税收优惠（每增加500美元）会使孩子在12月最后一周而非1月第一周出生的概率提高26.9%，说明税收激励影响生育时机。
Because the tax savings of having a child are a realized only if the birth takes place before midnight, January 1, the incentives for the "marginal" birth are substantial. Using a sample of children from the National Longitudinal Survey of Youth, we find that the probability that a child is born in the last week of December, rather than the first week of January, is positively correlated with tax benefits. We estimate that increasing the tax benefit of having a child by $500 raises the probability of having the child in the last week of December by 26.9 percent.