Between 1996 and 2022, regulatory changes led to over a thousand federally chartered credit unions converting to community charters, significantly increasing credit union membership. This study attempts to determine whether these developments improve safety and soundness by enabling credit unions to diversify their loan portfolios, or whether risk increases as the social capital of a tight common bond becomes diluted. We use two-way fixed effects, doubly robust and generalized synthetic control methods with state chartered credit unions and commercial banks as controls to estimate both intent-to-treat (ITT) and average treatment-effect-on-the-treated (ATT) impacts on credit union risk and returns. We find that conversions to community charter unambiguously improve credit union returns but the effects on risk are mixed: liquidity and capital fall, but there is no change in indicators of asset quality. Overall, during the 25-year period from 1998 to 2022, only 1.47% of community-chartered credit unions failed. The results suggest that social capital is no longer an important factor in reducing credit risk in countries with developed financial sectors like the U.S.

中文翻译：

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会员扩张对信用合作社风险和回报的影响

1996 年至 2022 年间，监管变化导致超过 1000 家联邦特许信用社转为社区特许社，大幅增加了信用社会员数量。本研究试图确定这些发展是否通过使信用合作社能够使其贷款组合多样化来提高安全性和稳健性，或者是否会随着紧缩的普通债券的社会资本被稀释而增加风险。我们使用双向固定效应、双稳健和广义综合控制方法，以州特许信用合作社和商业银行作为控制，来估计治疗意向 (ITT) 和治疗的平均治疗效果 (ATT)对信用社风险和回报的影响。我们发现，转换为社区章程无疑提高了信用合作社的回报，但对风险的影响是复杂的：流动性和资本下降，但资产质量指标没有变化。总体而言，从 1998 年到 2022 年的 25 年期间，只有 1.47% 的社区特许信用社倒闭。研究结果表明，在美国等金融业发达的国家，社会资本不再是降低信用风险的重要因素