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Tobias Adrian and Markus K. Brunnermeier 1 Current financial regulation Risk of each bank in isolation Value at Risk 1. Capital requirements 1% Haircuts/margins Ratings VaR Procyclical of capital requirements,


  1. Tobias Adrian and Markus K. Brunnermeier 1

  2. Current financial regulation Risk of each bank in isolation Value at Risk 1.  Capital requirements 1%  Haircuts/margins  Ratings VaR Procyclical of capital requirements, haircuts, ratings 2. Focus on asset side of the balance sheet 3. Liability side – maturity mismatch gets little attention  Maturity rat race  Implicit subsidies for short-term funding Focus on banks – 4. shadow banking system gets little attention 2

  3. Three challenges …. 1. Focus on externalities – systemic risk contribution  What are the externalities?  Regulate based on externalities (functional citerion)  How to measure externalities (contribution to systemic risk)?  CoVaR 2. Countercyclical regulation  Avoid procyclicality  leverage, maturity mismatch,… predict future CoVaR 3. Incorporate funding structure asset-liability interaction, debt maturity, liquidity risk 3

  4. 1. Externalities “stability is a public good” Fire-sale externality 1.  Maturity mismatch + Leverage liquidity F UNDING L IQUIDITY  Raise new funds (rollover risk) M ARKET L IQUIDITY  Sell off assets (at fire sale prices due to crowded trades) Fire-sales depress price also for others 1. Hoarding externality 2. Bank 2  micro-prudent response: A | L Hoard funds/reduce lending  … but not necessarily macro-prudent Bank 3 Bank 1  Systemic risk is endogenous (multiple equl) A | L A | L Runs – dynamic co-opetition 3. Network Externality 4.  Hiding own’s commitment uncertainty for counterparties See Brunnermeier (2009) Journal of Economic Perspectives

  5. 2. Procyclicalitydue to Liquidity spirals  Loss spiral  same leverage  mark-to-market Reduced Positions  Margin/haircut spiral  Margin/haircut Initial Losses Funding Liquidity Market Liquidity max leverage e.g. credit Problems Prices Deviate  The more short-term, the lower margin/haircut Higher Margins  delever!  mark-to-model Losses on Existing Positions Brunnermeier-Pedersen (2009)  Mark-to-funding

  6. Margin/haircut spiral -Procyclicality  Margins/haircut increase in times of crisis delever margin = f(risk measure)  Three reasons: Backward-looking estimation of risk measure 1.  Use forward looking measures ? Great moderation = great complacency  Use long enough data series Fundamental volatility increases 2. Adverse selection 3.  Debt becomes more information sensitive (not so much out of the money anymore) cash flow  Credit bubbles  whose bursting undermines financial system Countercyclical regulation

  7. Margin/haircut spiral -Procyclicality  Margins/haircut increase in times of crisis delever margin = f(risk measure)  Three reasons: Backward-looking estimation of risk measure 1.  Use forward looking measures  Use long enough data series Fundamental volatility increases 2. Adverse selection 3.  Debt becomes more information sensitive (not so much out of the money anymore) cash flow  Credit bubbles  whose bursting undermines financial system Countercyclical regulation

  8. Credit/Leverage Bubble  Why did nobody delever/act against it earlier?  “dance as long as the music plays”  Lack of coordination when to go against the bubble  Not riding a bubble for too long is … can cost you your shirt  Even if one identify bubbles, predicting the time of its bursting is infinitely more difficult  Investors/institutions ride the bubble which allows it to persist  Little heterogeneity  Credit bubble led to housing bubble  Note similarity to Nordic countries, Japan,… (foreign capital, agency problems were less of an issue there) 11

  9. Macro-prudential regulation Externality: 1.  Measure contribution of institution to systemic risk: CoVaR  Response to current regulation “hang on to others and take positions that drag others down when you are in trouble” (maximize bailout probability Moral Hazard )  become big  hold similar position (be in trouble when others are)  become interconnected Procyclicality: 2.  Lean against “credit bubbles” – laddered response  Bubble + maturity mismatch impair financial system (vs. NASDAQ bubble)  Impose Capital requirements/Pigouvian tax/Private insurance scheme  not directly on ∆ CoVaR, but on  frequently observed factors, like maturity mismatch, leverage, B/M, crowdedness of trades/credit, … Funding: Asset-Liability Maturity Match 3.

  10. Who should be regulated? group examples macro-prudential micro-prudential “individually International banks Yes Yes systemic” (national champions) “systemic as part of Leveraged hedge Yes No a herd” funds non-systemic large Pension funds N0 Yes “ tinies ” unlevered N0 No  Micro: based on risk in isolation  Macro: Classification on systemic risk contribution measure, e.g. CoVaR  Annual list (not publicized) 14

  11. CoVaR  i is implicitly defined as quantile CoVaR q i i Pr( ) X VaR q q j|i is the VaR conditional on  CoVaR q institute i (index) is in distress (at it’s VaR level) | j j i i i Pr( | ) X CoVaR X VaR q q q j|i -VaR q  Δ CoVaR q j|I = CoVaR q j  Various conditioning possibilities? (direction matters!)  Contribution Δ CoVaR  Q1: Which institutions contribute (in a non-causal sense)  VaR system | institution i in distress  Exposure Δ CoVaR  Q2: Which institutions are most exposed if there is a systemic crisis? VaR i | system in distress   Network Δ CoVaR Can be extended to  VaR of institution j conditional on i Co-Expected Shortfall!

  12. Network CoVaR 270 122 70 49 67 116 72 72 564 68 50 118 357 76 247 116 133 50  conditional on origin of arrow 57 108

  13. Overview  Challanges  Measuring Systemic Risk Spillover/Externalities  One Method: Quantile Regressions  CoVaR vs. VaR  Addressing Procyclicality  Predict using institutions’ characteristics  Balance sheet variables  Market variables (CDS, implied vol.,…) 18

  14. QuantileRegressions: A Refresher  OLS Regression: min sum of squared residuals 2 OLS arg min y x t t t [ | ]  Predicted value: E y x x  Quantile Regression: min weighted absolute values if 0 q y x y x t t t t q argmin t 1 if 0 q y x y x t t t t 1 | ( | ) VaR x F q x x  Predicted value: q y q q 19 Note out (non-traditional) sign convention!

  15. QuantileRegression: A Refresher q-Sensitivities 5 0 -5 -10 -10 -5 0 5 10 CS/Tremont Hedge Fund Index Fixed Income Arbitrage 50%-Sensitivity 5%-Sensitivity 1%-Sensitivity 20

  16. Financial Intermediary Data  Publicly traded financial intermediaries 1986-2008  Commercial bank, security broker-dealers, insurance companies, real estate companies, etc.  Weekly market equity data from CRSP  Quarterly balance sheet data from COMPUSTAT  CDS and option data of top 10 US banks, daily 2004-2008 22

  17. Overview  Measuring Systemic Risk Contribution  One Method: Quantile Regressions  CoVaR vs. VaR  Addressing Procyclicality  Time-varying CoVaR/VaR  Predict using institutions’ characteristics  Balance sheet variables  Market variables (CDS, implied vol.,…) 24

  18. Δ CoVaRvs. VaR  VaR and ¢ CoVaR relationship is very weak  Data up to 12/06 25

  19. Overview  Challanges  Measuring Systemic Risk Contribution  One Method: Quantile Regressions  CoVaR vs. VaR  Addressing Procyclicality  Step 1: Time-varying CoVaRs  Step 2: Predict CoVaR using institution characteristics  Balance sheet variables (leverage, maturity mismatch, + interdependence, …)  Market variables (CDS, implied vol.,…) 28

  20. Step 1: Time-varying CoVaR  Relate to macro factors, M t interpretation  VIX Level “Volatility”  3 month yield  Repo – 3 month Treasury “Flight to Liquidity”  Moody’s BAA – 10 year Treasury “Credit indicator”  10Year – 3 month Treasury “Business Cycle”  Real estate index “Housing”  Equity market risk  Obtain Panel data of CoVaR  Next step: Relate to institution specific (panel) data 29

  21. Step 1: Time-varying Δ CoVaR  Derive time-varying VaR t  For institution i : i i i i X M t q q t t  For financial system: system system system system X M t q q t t  Derive time-varying CoVaR t | | | system system i system i i system i X M X t q q t t t  Δ CoVaR t = CoVaR t -VaR t 30

  22. Table 2: Average Exposures to Risk Factors INSTITUTIONS COEFFICIENT VaR system VaR i CoVaR system|i Repo spread (lag) -1163*** -0.60 -877.94*** Credit spread (lag) -107.75 -0.47 -226.75** Term spread (lag) 128.71 0.64 18.80 VIX (lag) -68.97*** -0.16*** -43.35*** 3 Month Yield (lag) 118.73 0.42 15.95* Market Return (lag) 242.74*** 0.50*** 196.00*** Housing (lag) 5.63 0.03 5.17 *** p< 0.01 ** p< 0.05 * p< 0.1 31

  23. Time-varying VaR Commerical Bank VaR 20 0 -20 -40 -60 1985w1 1990w1 1995w1 2000w1 2005w1 2010w1 Asset Change VaR 34

  24. Time-varying VaRand Δ CoVaR Commerical Bank VaR and Delta CoVaR 20 0 0 Delta CoVaR -1000 -20 -2000 -40 -3000 -60 1985w1 1990w1 1995w1 2000w1 2005w1 2010w1 Asset Change VaR Delta CoVaR 35

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