理想生育率、实际生育率与中国全面二孩政策的影响

中文摘要

我们认为, 在低生育率情境下, 女性的期望生育率已成为约束性限制: 一旦生育意愿降至政策上限之下, 仅取消配额便无法带来显著反弹。我们利用中国于2016年1月实施的全面二孩政策来检验这一假说——该政策是在独生子女政策持续数十年之后突然推行的一项全国性放宽。基于2017年中国生育状况调查的全国代表性数据, 并利用全面二孩政策所产生的资格差异, 我们发现该政策在2016—2017年仅使每名符合资格女性的出生数增加0.023, 且这一增长几乎完全由期望生育两个或更多孩子的女性驱动。来自2020年人口普查数据的县级证据进一步显示, 2016—2020年的生育率上升主要发生在平均期望生育率较高的地区。这些结果表明, 在后独生子女政策时期的中国, 约束生育率的已是下降的生育意愿, 而非行政性生育配额。

Abstract

We argue that women’s desired fertility has become the binding constraint in low-fertility contexts: once fertility desires fall below policy ceilings, removing quotas alone cannot generate a substantial rebound. We test this hypothesis using China’s Universal Two-Child (UTC) policy adopted in January 2016, an abrupt nationwide relaxation following decades of the One-Child Policy (OCP). Drawing on nationally representative data from the 2017 China Fertility Survey and exploiting eligibility variation created by the UTC policy, we find that the policy increased births by only 0.023 per eligible woman in 2016–2017, driven almost exclusively by women who desired two or more children. County-level evidence from the 2020 population census data further shows that fertility in 2016–2020 rose primarily in places with higher average desired fertility. These results indicate that declining fertility desires—not administrative birth quotas—now constrain fertility in post-OCP China.