Systemic Risk
Systemic risk is the risk that the failure or distress of one institution, market, or instrument spreads through interconnections until the financial system as a whole stops performing its core functions of credit, payments, and risk transfer. The official 2009 IMF/BIS/FSB definition frames it as a risk of disruption to financial services that is (i) caused by an impairment of all or parts of the system and (ii) has the potential for serious negative consequences for the real economy. It is a property of the whole network, not of any single firm in isolation, which is why it requires macroprudential oversight rather than purely firm-by-firm supervision.
Why it matters
Think of a power grid. One overloaded substation can be handled locally, but if the substations are wired tightly together, one failure cascades into a region-wide blackout. Finance is wired the same way through interbank loans, shared collateral, and common exposures. Systemic risk is the blackout risk of the financial grid: the danger is not that a bank can fail, but that its failure trips everyone else and the lights go out for the real economy.
Formulas
Worked examples
In September 2008 Lehman Brothers, a single investment bank, filed for bankruptcy. Why did regulators treat this as a system-wide event rather than one firm’s failure?
Lehman was a counterparty to thousands of derivatives and repo trades. Its default froze short-term funding markets, broke the Reserve Primary money-market fund (which "broke the buck"), and triggered a global flight from risk. The loss to the system, through frozen credit and fire sales, vastly exceeded Lehman’s own balance-sheet loss. That amplification through interconnection is the defining mark of systemic risk.
In March 2020 the COVID-19 shock hit. Why was it a systemic event even though the trigger was a virus, not a bank?
A real-economy shock forced a simultaneous "dash for cash": funds sold even US Treasuries to raise liquidity, dealer balance sheets clogged, and core markets seized. The shock propagated through the financial network and threatened payments and credit, so central banks intervened at scale. Systemic risk is about the channel of propagation, not the original trigger.
Common mistakes
- ✗Systemic risk is just the risk that a big bank fails. The failure is only the trigger. Systemic risk is the propagation through interconnections that turns one failure into a system-wide breakdown.
- ✗Systemic risk and systematic (market) risk are the same thing. They are different concepts; see the dedicated systemic-vs-systematic node. Systematic risk is non-diversifiable market-wide risk in asset pricing, while systemic risk is the risk of financial-system collapse via contagion.
- ✗If every individual bank is sound, the system is automatically safe. The fallacy of composition: actions that are prudent for one firm, such as selling assets to deleverage, can be destabilizing when all firms do them at once.
- ✗Only banks can be systemically important. A non-bank can be too. In 1998 the hedge fund Long-Term Capital Management, with vast leveraged derivatives positions across major dealers, threatened the system, prompting a Federal-Reserve-organized recapitalization (about $3.6 billion) by 14 financial firms even though no public money was lent.
Revision bullets
- •Risk that one failure disrupts the whole financial system, harming the real economy
- •Official IMF/BIS/FSB (2009) definition: impairment of financial services with real-economy spillovers
- •A network property, not a single-firm property
- •Amplified by interconnection so system loss exceeds the sum of standalone losses
- •Requires macroprudential, not just firm-by-firm, supervision
Quick check
According to the 2009 IMF/BIS/FSB definition, systemic risk is best described as the risk of
Why can a financial system be unstable even when each individual bank looks sound in isolation?
Connected topics
Sources
- International Monetary Fund, Bank for International Settlements, and Financial Stability Board. Guidance to Assess the Systemic Importance of Financial Institutions, Markets and Instruments: Initial Considerations. Report to the G-20 Finance Ministers and Central Bank Governors, October 2009.Source of the canonical definition of systemic risk and systemic importance.
- Acharya, V. V., Pedersen, L. H., Philippon, T., and Richardson, M. "Measuring Systemic Risk." Review of Financial Studies 30 (1), 2017, 2-47.Formalizes systemic risk as a negative externality and motivates the MES/SRISK framework.
- Federal Reserve History. "Near Failure of Long-Term Capital Management, 1998." Federal Reserve Bank of Richmond / Federal Reserve History project.Account of the 1998 LTCM episode: a single leveraged fund posing systemic risk and the Fed-organized private recapitalization.