中国银行业净息差与非利息收入的关系研究

The Relationship between Net Interest Margin and Non-interest Income for Chinese Banks

本文立足于我国利率未完全市场化的背景,构建了利率管制下的商业银行最优净息差与非利息收入的理论模型,得到了净息差与非利息收入是共同决定、相互影响且影响程度与银行属性相关的理论结果。以此为基础,本文采用1998—2012年中国银行业的微观数据,对中国银行业的净息差与非利息收入之间的相互关系进行了实证检验。结果表明:净息差与非利息收入在我国银行业总体中互为负向的替代关系,在不同类型的银行中存在显著差异。对于大型国有银行,非利息收入对净息差的正向影响并不显著,净息差对非利息收入为显著的负向影响;对于全国性股份制银行,净息差与非利息收入之间的影响关系互为不显著的正向关系;而对于地方性商业银行,这一相互影响关系显著为负。最后,本文从银行微观经营层面提出了相应的建议。

Based on the background of strict interest-rate control in China, we construct an optimal pricing model for commercial banks taking non-interest income into account and prove that net interest margin and non-interest income are jointly determined, and the degree of impact depends on the ownership of the bank. We use micro data from Chinese banks during 1998--2012 and empirically test the relationship between net interest margin （NIM） and non-interest income （NII）. The empirical results show that, the relationship between NIM and NII is negative for the whole sample is significantly different for banks of different ownerships. For state-owned banks, the impact of NIl on NIM is insignificantly positive, while the impact of NIM on NII is negative. For joint-stock banks, the relationship between NIM and Nil is insignificantly positive, while for local banks, the relationship is negative. Lastly, we propose several policy recommendations from the perspectives of bank management and supervision.