Econ Papers Daily / 期刊论文
人口老龄化对自然利率的动态效应
Dynamic Effects of Population Aging on Natural Interest Rates
摘要
Declining fertility and rising longevity are accelerating population aging worldwide. We study their effects on interest rates using a quantitative life-cycle model that explicitly accounts for the long lag between birth and labor-market entry, and features Barro-Becker parental preference, endogenous human capital accumulation, and a public pension system. Reducing fertility raises the interest rate during a sustained transition, as agents increase consumption in anticipation of future labor shortages and wage growth, before converging to a lower steady state. Increasing longevity instead monotonically reduces the interest rate by raising precautionary savings. These divergent dynamics are robust to variations in the pension system, human capital inputs, and child-related allocations. A historical decomposition further shows that fertility shocks have been the dominant demographic driver of U.S. interest rate fluctuations since 1960. These findings challenge the view that aging uniformly lowers interest rates and highlight the distinct implications of fertility- and longevity-driven aging.
中文摘要
生育率下降与寿命延长正在加速全球人口老龄化。本文运用一个量化生命周期模型研究二者对利率的影响，该模型明确考虑了出生与进入劳动力市场之间的长滞后，并具有巴罗-贝克尔父母偏好、内生人力资本积累和公共养老金制度等特征。在持续转型期间，生育率下降会推高利率，因为个体预期未来劳动力短缺和工资增长而增加消费，随后收敛至较低的稳态。相反，寿命延长通过提高预防性储蓄而单调降低利率。这些分化动态在养老金制度、人力资本投入和与子女相关的资源配置发生变化时依然稳健。历史分解进一步表明，自1960年以来，生育冲击一直是美国利率波动的主要人口驱动因素。这些发现挑战了老龄化会一致降低利率的观点，并凸显了生育率驱动型老龄化与寿命驱动型老龄化的不同含义。