2023-03-28-IMF-美国货币政策对非银行金融的异质性影响（英）_43页_3mb

The Heterogeneous Effects of U.S. Monetary Policy on Non-Bank Finance: Summary

This IMF working paper examines the effects of U.S. monetary policy shocks on the non-bank financial sector, particularly focusing on differences over time and across institutional segments. The key findings can be summarized as follows:

1. Introduction

• The structure of the U.S. financial system has evolved significantly, with non-bank finance growing substantially. Regulatory changes have also influenced the intermediation activities of these institutions.
• While non-banks were linked to periods of instability (e.g., the Global Financial Crisis (GFC), 2020 liquidity crisis), their role has expanded through the development of private asset-backed securities (ABS).

2. Non-Bank Financial Sector: Stylized Facts

Measurement Approaches

• Two primary approaches for measuring non-bank size are used:
  • Institutional Approach: Sums liabilities of institutions relying on short-term funding (e.g., mutual funds, repo).
  • Functional Approach: Consolidates intermediation chains to avoid double-counting, providing a measure of credit intermediation to the real economy. This measure shows the non-bank sector, especially the short-term funding segment, grew before the GFC, declined afterward, and has seen divergence between institutional and functional measures since the pandemic began.

Regulatory Context

• Post-GFC regulatory reforms (Dodd-Frank Act) aimed to increase oversight of non-banks, though traditional banks remain more regulated.
• Regulatory focus has included addressing money market funds, hedge funds, and private equity under frameworks like the Financial Stability Oversight Council (FSOC).

3. Monetary Policy Identification

• Policy shocks are identified using methods such as the Jarociński and Karadi (2020) future rate surprises, distinguishing between contractionary monetary shocks and informational shocks (Fed information signals) to avoid conflating macroeconomic signals with pure monetary policy.

4. Impact on Non-Bank Size

• Using local projections and Vector Autoregression (VAR) techniques, it is found that:
  • Short-term non-bank finance (subject to run risks) expands under contractionary monetary policy, showing a "dislocation" effect—an incentive to shift intermediation to institutions with access to cheaper short-term funding, including through asset securitization.
  • Long-term non-bank finance contracts during contractionary periods, especially in the post-GFC era, likely reflecting substitution effects and lower profitability among institutions using stable funding.

5. Impact on Flows and Returns into Non-Bank Funds

• Focusing on long-term mutual funds (bond and equity), tight monetary policy leads to:
  • Significant outflows, particularly from high-yield bonds and international equity funds.
  • Declines in returns, influenced by portfolio rebalancing and risk aversion effects.

6. Time-Varying Effects (MS-VAR)

• Modeling through Markov Switching VARs shows:
  • The contractionary effect on long-term non-banks increased after the GFC. Before the crisis, contractionary shocks reduced flows to long-term funds.
  • The "dislocation effect" (stimulation of short-term non-bank growth via monetary tightening) is more prominent post-2007, reflecting shifts including regulatory changes and market innovations.

7. Conclusion

• U.S. monetary policy has heterogeneous effects across the non-bank sector. Contractionary policy generally shrinks assets dependent on long-term funding while boosting those reliant on short-term funding.
• The analysis suggests that regulatory frameworks and macroeconomic conditions influence the transmission mechanisms of monetary policy. These findings highlight the importance of evolving monetary policy strategies to account for non-bank pathways into the economy and potential risks, especially for institutions prone to run risks. Further research is needed on the drivers and systemic implications of these transmission changes.