2023-12-06-IMF-投资组合选择模型中的央行数字货币与银行去中介_50页_1mb

Central Bank Digital Currency and Bank Disintermediation in a Portfolio Choice Model Summary

Key Findings:

1. Bank Deposit Disintermediation:

   • The introduction of CBDC can lead to a reduction in bank deposits due to a "wide margin" effect, where poorer households abandon deposits in favor of CBDC due to lower access costs.
   • The magnitude of disintermediation depends on household wealth distribution, CBDC accessibility, and the relative costs of accessing deposits and CBDC. A larger share of poorer households can amplify this effect.
   • Even with deposit disintermediation, aggregate deposits may still increase or decrease depending on bank responses and fixed costs.

2. Quantitative Effects:

   • Using U.S. data, the model shows that CBDC introduction leads to about a 4% decrease in total deposits when access barriers are high.
   • Results vary with bank market power and the wealth distribution parameter α. Disintermediation is more pronounced in economies with a higher proportion of poorer households.

3. Impact on Lending:

   • Bank disintermediation due to CBDC has minimal quantitative impact on lending (less than 0.2%), as banks can substitute wholesale or central bank funding to offset lost deposits.
   • Bank profitability decreases due to reduced net interest margins, but lending remains relatively resilient.

4. Policy Implications:

   • The design of CBDC must consider barriers to bank deposit access and varying household preferences to avoid significant disintermediation.
   • Policymakers need quality data on household preferences and financial inclusion to assess CBDC's effects accurately.

Conclusion:

CBDC introduction may reduce bank deposits in some scenarios due to substitution effects, but its impact on lending is quantitatively small if banks have alternative funding sources. The effects are determined by household heterogeneity, market structure, and bank responses. While CBDC can enhance financial inclusion, designing it requires careful consideration of competition and access costs to mitigate bank disintermediation risks.