Progressive Child Allowance as a Countermeasure to the Declining Number of Births

本稿では、簡易なOLGモデルを構築し、少子化対策に割り当てられる財源に一定の制約があるなか、賦課方式年金の存在を前提に、定常状態における家計の効用を最大化する累進型の子ども手当などに関する分析をしている。分析の結果、次のことが明らかになった。1）定常状態における家計の効用を最大にする出生数は、累進型の子ども手当を適切に導入することで実現でき、少子化対策の予算が少ない場合ほど、子ども手当の累進度を高めるのが望ましいということ、2）線形の子ども手当でも、定常状態における家計の効用を最大にする出生数を実現できるが、累進型の子ども手当と異なり、本稿の具体的な数値例では、少子化対策の予算規模を超過してしまう可能性があること等である。

This article constructs a simple overlapping generations (OLG) model to analyze the progressive child allowance and related policies with the objective of addressing the declining number of births in Japan. The analysis assumes the existence of a pay-as-you-go pension system and a certain constraint on fiscal resources. The focus is on maximizing household utility in the steady state. Results of the analysis reveal the following findings: 1) The number of births that maximizes household utility in the steady state can be achieved by appropriately introducing a progressive child allowance. Moreover, the smaller the budget necessary to implement and support measures to address the declining number of births, the more desirable it is to increase the progressivity of the child allowance. 2) A linear child allowance can also achieve the number of births that maximizes household utility in the steady state. However, unlike the progressive child allowance, by taking the example of Japan, the specific numerical examples presented in this article demonstrate that the linear child allowance may exceed the available budget for such measures.