《保险研究》20240109-《最低缴费年限调整、居民参保意愿与基本养老保险基金可持续性研究》（于新亮、任丽颖）

［摘   要］本文基于“缴费年限-参保意愿-基金可持续性”理论框架，使用中国家庭金融调查(CHFS)数据库，实证检验提高最低缴费年限对居民参保意愿和缴费水平产生的影响，进而将该影响参数纳入城乡居民基本养老保险基金精算模型，测算在财政适度范围内有效提高基金可持续性的最优缴费年限。研究发现：提高最低缴费年限与居民参保意愿呈现倒“U”型关系，拐点为5.88年，同时会降低缴费水平，边际效应为1.14个百分点；提高最低缴费年限虽然能够增强城乡居民基本养老保险可持续性，但对财政负担产生差异性影响，其中提高6年时可在财政负担承受范围内最大限度提高基金可持续性。据此，本文提出最低缴费年限以21年为最优，为“逐步提高领取基本养老金最低缴费年限”的具体实施提供证据参考。

［关键词］多层次养老保障体系；养老保险基金可持续性；最低缴费年限；两部模型

［基金项目］本文受国家自然科学基金面上项目“长期护理保险嵌入农村医养健康服务体系的传导机制、福利效应和路径优化研究”(72274104)、国家自然科学基金青年科学基金项目“灾难性卫生支出的风险识别、致贫路径与精准保障研究”(71804090)、首都医科大学国家医疗保障研究院开放性课题“多层次长期护理保障体系问题研究”(YB2023B06)、泰山学者工程专项经费的资助。

［作者简介］于新亮（通讯作者），山东财经大学保险学院教授、博士生导师；任丽颖，山东财经大学保险学院硕士研究生。

Minimum Contribution Period Adjustment，Participation Willingness and Sustainability of the Urban and Rural Residents Basic Pension Insurance

YU Xin-liang，REN Li-ying

Abstract：Based on the theoretical framework of “contribution period-willingness to participate-fund sustainability”，this paper uses the database of China Household Finance Survey (CHFS) to empirically test the impact of increasing the minimum contribution period on residents′ willingness to participate in the urban and rural basic pension insurance and the level of contribution.It then incorporates this parameter into the actuarial model of the basic pension insurance fund for urban and rural residents，and measures the optimal number of years of contributions that can effectively improve the sustainability of the fund within the moderate fiscal range.The study finds that raising the minimum number of years of contributions has an inverted U-shaped relationship with residents′ willingness to participate in insurance，with an inflection point of 5.88 years，and at the same time reduces the level of contributions，with a marginal effect of 1.14 percentage points.Although raising the minimum contribution period can enhance the sustainability of basic pension insurance for urban and rural residents，it has a differentiated impact on the fiscal burden，in which raising the minimum contribution period by 6 years can maximize the sustainability of the fund within the scope of the fiscal burden.Accordingly，this paper proposes that 21 years is the optimal minimum contribution period，thus providing evidences for the implementation of “gradually increasing the minimum contribution period for receiving basic pensions”.

Key words：multi-level pension system;sustainability of the pension fund;minimum contribution period;two-part model