We compare the 2007–2009 post-financial-crisis performance of US banks with their performance before the financial crisis, based on bank size using financial ratios. We find bank performance declined in the post-financial-crisis period as compared to its pre-financial-crisis performance, evidenced by reduced return on equity (ROE) and return on assets (ROA), higher debt ratios, lower net interest margin, increased net loan losses, more nonperforming loans, and, to a lesser extent, estimated losses on loans. In difference-in-differences tests between the largest and smallest groups, we find the biggest banks report significantly higher ROA and lower debt ratio, in addition to outperforming small banks in net interest margin and loan loss reserves. Smaller banks did better only in net loan losses. General economic conditions and interest rate changes are controlled for in our results. We conclude that small banks have a significant disadvantage in the industry in the post-financial-crisis era compared to both big banks and their own pre-financial-crisis historical performance.

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银行规模与业绩：后金融危机时代美国银行业分析

我们根据银行规模，使用财务比率，将美国银行 2007 年至 2009 年金融危机后的表现与金融危机前的表现进行了比较。我们发现，与金融危机前的表现相比，后金融危机时期的银行业绩有所下降，表现为股本回报率 (ROE) 和资产回报率 (ROA) 降低、债务比率升高、净息差降低、净贷款损失增加，不良贷款增加，以及在较小程度上估计贷款损失。在最大和最小组之间的差异测试中，我们发现最大的银行报告显着更高的资产回报率和更低的负债率，此外在净息差和贷款损失准备金方面的表现优于小银行。小型银行仅在净贷款损失方面表现更好。我们的结果控制了一般经济状况和利率变化。我们得出的结论是，与大银行及其金融危机前的历史表现相比，小银行在后金融危机时代在该行业中处于显着劣势。