Title: Prof Sudipto Bhattacharya, LSE
1Prof Sudipto Bhattacharya, LSE
- Banks, Liquidity Crunches (to Crises) and
Multiple Dimensions of Moral Hazards in the
Regulated Economy
2I Liquidity versus Risk-Shifting
- Banks moral hazard w.r.t under-investment in
liquid (shorter maturity) assets, happens to be
just QUALITATIVELY DIFFERENT from that vis-Ã -vis
Excessive Risk-Taking - For example, lower Bank borrowing rates encourage
over-investment in ILLIQUID longer-maturity
assets, even with perfect secondary markets for
these, whereas THE
3Some Lessons for Policy Makers
- OPPOSITE IS TRUE for RISK-SHIFTING by banks with
(in effect) insured depositors it is HIGHER bank
borrowing rates which lead to more/excessive
risk-taking by them - Indeed, there is NO JUSTIFICATION FOR Punitive ex
post Interest Rates on Loans to Banks judged to
be suffering from External- caused Liquidity
Shocks, although there IS
4Re What to Do in out of Crises
- A CLEAR RATIONALE FOR HAVING A CENTRAL-BANK RUN
INTERBANK - BORROWING-LENDING FACILITY with
- Clear Pre-committed Borrowing Limits, and
- Reserve Requirements for Internal Liquidity
Provisions at Each Member Bank, which is
completely de-linked from Macroeconomic Price
Stability (Bhattacharya Gale, 1987)
5II. When a Crunch is Systemic
- Based on Diamond and Rajan in JoF, 2005
- Two types of Banks A with 40 of Loans repayable
early, 60 after one period, and B with the
opposite. Each (long-term) loan of 1 generates
investment returns of 1.6 if not liquidated
early, of which bankers can collect 80, or 1.28
per loan. On the other hand, if liquidated early,
each loan yields
6What Should Policymakers Do?
- 0.4 immediately, and 0.5 after one period in
alternative uses (transfers to other owners) - A bad (but not necessarily disastrous!) state of
the economy has 60 of banks in the A category,
and 40 in the B category, where - Depositors have Demandable Claims, and come to
learn about their banks states just before even
better bank loans can be repaid
7Support Creation of Liquidity, or
- NON-destruction thereof, VIA MARKETS!
- Total available resources in the banking system
to pay depositors in the first period without
transfering/restructuring bank loans is 0.60.4
0.40.61.6 .768, which is INSUFFICIENT TO
MEET DEPOSITOR DEMANDS OF UNITY, even with banks
fortunate borrowers investing/re-depositing
8Process of Orderly Restructuring
- Thus 0.232 of additional liquidity MUST be
created via restructuring of Bank Loans. Is it
the case that (inter-bank with investors in it
too) MARKETS WILL DO THAT OK? - The answer is NO at any interest rate above 1.4,
A-type banks would be insolvent even after
restructuring, leading to EARLY (good quality)
LOANS being RESTRUCTURED
9B-TYPE BANKS WONT HELP
- Via restructuring their loans too to create
additional short-term liquidity unless inter-
bank interest rates rise to 1.6, BUT THAT - IS EXACTLY WHAT THEY WOULD DO because attempted
(forced) Restructuring by the Run A-type BANKS
WOULD DRAIN LIQUIDITY AWAY WHEN B-banks try to
PARTIALLY restructure, which they must
10IN THEIR MYOPIC ACTIONS
- ALBEIT IN A SMALL way only in that as 60 of
their loans realised early, their loan base, of
repayments PLUS investment by the lucky
borrowers, CAN contribute THE AMOUNT 0.61.6
.96 in the first period - BUT THESE INVESTORS WOULD BUY THE the
restructured A-BANK LOANS as well, so the B
banks would need to liquidate
11IGNORING SYSTEMIC RISKS
- More loans, and INTEREST RATES WILL RISE ABOVE
1.95, CAUSING THEM TO BE INSOLVENT AS WELL,
WHEREAS - IF THE GOVERNMENT FACILITATED restructuring of
loans by the more illiquid banks, at a Gross
Interest Rate BELOW 1.4, they and its lucky
borrowers together would need to buy .6.6.5of
future restructured
12ARISING FROM SPILLOVERS
- LOAN PAYOFFS, .18 FROM UNLUCKY BANKS. THAT and
.016 liquidity injection to B-BANKS, would be
partially provided BY THE NON-LIQUIDATED (LUCKY)
BORROWERS OF THE UNLUCKY A- BANKS, THUS REQUIRING
POLICY MAKERS TO INJECT VERY LITTLE AS SUBSIDY
TO THE UNLUCKY BANKS!
13HOW MUCH GOVERNMENT SUBSIDY WILL BE NEEDED?
- To preclude runs that would require them to
restructure even their early-realised loans, A
banks need to obtain liquidity injection of
1-.4(1.28)- .6(0.4) 0.248 each, additional to
cash they obtain from restructured loans. - If they do so with ALL late loans, B-banks will
not need to restructure any of their late loans
lucky borrowers will fund them anew
14MAKING USE OF A PRIVATE CUM PUBLIC PARTNERSHIP
- A-BANKS HAVE 0.60.5 OF FUTURE PAYOFFS FROM THE
RESTRUCTURED LOANS TO PUT UP AS COLLATERAL. - FOR BUYING THESE RESTRUCTURED LOANS, THEIR LUCKY
BORROWERS CAN PUT UP A TOTAL OF .24(.32) - .4
.04 .061, AFTER ADDING LIQUIDITY TO FUND
WITHDRAWAL AT B-BANKS
15WITH HIGH SOCIAL RETURN
- Thus the GOVERNMENT NEED ONLY PROVIDE (.6.248)
- .061 .088, AND - THEREBY ENSURE INTEREST RATES DO NOT RISE ABOVE
.3/.248 1.21, OR 21 NET, SO THAT A-BANKS STAY
SOLVENT,i.e., THEY CAN MEET THEIR - DEPOSITORS EARLY WITHDRAWAL DEMANDS, OF UNITY AT
EACH BANK
16INSOFAR AS GOVERNMENT
- LIQUIDITY INJECTION OF .088 EARNS THE RESPECTABLE
RETURN OF 21 NET, AND ENDS UP PREVENTING THE - ADDITIONAL RESTRUCTURING OF .6 .4 .24 OF
EARLY-REALISED LOANS - THIS GENERATES A SOCIAL SURPLUS OF AT LEAST .24
(1.6 - 0.4 - 0.5).168 A SPECTACULAR POLICY
SUCCESS!!
17WHAT THEY AND I DONT
- KNOW is, myopia as above aside, WHY FLIGHT TO
QUALITY OF BANKS IN SUCH CIRCUMSTANCES IS SO
MUCH! - 64 BILLION QUESTION IS is it fear of adverse
selection on the restructured loans? - IT IS NOT EXPLAINABLE VIA BANKS ENSURING ADEQUATE
CAPITAL per se
18EXCEPT HISTORICALLY
- WHEN even during the Great Depression in USA,
aggregate volume of Bank Deposits in banks
Subjected to Runs was around 5 of US Deposit
Base, but banks as a whole - Reduced their Loan-to Deposit ratios, from 85 or
so to around 55 over five years! - To need 30-35 in Reserves to Insure any Losses
on 55 in Loans, seems Excessive!
19WHAT THEY SHOULDVE KNOWN, HOWEVER IS
- THAT, AT LEAST FACED WITH SUCH EXTREME FLIGHTS
TO QUALITY BY - (LUCKIER) BANKS, OPTIMAL POLICY
- SHOULD HAVE BEEN TARGETED NOT AUCTIONED
LIQUIDITY INJECTIONS, SELECTIVELY TO THE LESS
LUCKY BANKS WHO MUST RESTRUCTURE, BUT STILL FAIL
W/O SUCH SUBSIDY
20Recent Banking Research on
- Loan Rollover and Credit Freezes
- Adverse Selection Impact Funding
- And Optimal Bank Bailout Policies
21Allen and Gale Rollover Risks
- Economy in One of Two States at Each of N Dates,
then a Terminal Date at T1 - Terminal Asset Payoffs are Zero if state then is
S1, and V gt 0 if it is S2. Earlier, - Asset is Funded ONLY with Debt, which
- Is Short-term, Subject to Default Risks
- States Evolve as a Markov Process with
22Given Transition Probabilities
- P,1-P from S1 to S1, S2 and 1-Q,Q from S2
to S1, S2 further, Q gt (1-P) - Pessimistic Scenario Q 1, P is small
- If there is Default on Debt, leading to an Asset
Sale, it realizes only a fraction f in 0,1) of
its next period pledgeable value - Examine Debt Capacity when N is large
23Maximum Debt Funding
- At date N, given the current state is S1, equals
V(1-P) its promised payment V - At date (N - 1), it becomes, based again on a
promised repayment D2 V, B2 (1-P)V
PfV(1-P) lt V(1 - P2), the expected value of
Terminal asset Payoff - Indeed, in the Limit as N goes to Infinity
24Holding Constant Credit Risk
- Or Probability of Default at the Terminal Date,
at PP(N)(N1) the Initial Debt - Funding Level BoV(1-P)/(1-fP), which
Approaches 0 given flt1 P(N) tends to 1 - In Contrast, if the Markovian evolution is
Optimistic, with Q in (0,1) and P 1, and the
current state is S2, Maximal Debt at
25Depends on Current Mood
- Funding Level at the initial date equals Bo
Q(N1)V, or EQUAL to Asset Value given
expected terminal payoff! - More generally, given BOTH P and Q in (0, 1) with
Q gt (1-fP), following are true - At any date, the Maximal Debt Funding level is
Higher when the Economy is in
26Or, The State of the Economy
- State S2 than when its in State S1, and
- The sub-Sequence of Maximal Funding Levels in S2
state are increasing across time as we approach
the terminal date - Whereas, the Opposite is True for the
sub-Sequence of Maximal Debt funding levels in S1
state A Crash vs a Bubble?
27The Credit Freeze Implication
- IS FRAGILE, if some Equity Capital is Available
as well, especially in S1 state - For example, in a Pessimistic Scenario with Q
1, and P in (0,1), the borrowing - Level in the final period would remain at B1
V(1-P), on promised repayment V - BUT, in the penultimate period, it would
28Need Not be Always Valid
- Be Optimal to issue only Safe Debt with Promised
Repayment D2 B1 V(1-P), to maximize Overall
Payoff Z2 (1-P) (V-D2)Pmax(B1- D2,0)
Proceeds of Debt Issue given D2 debt value B2
equals D2 only if its no higher than B1 - With three periods left, Safe Debt with a
Promised Repayment D3 Z2 can then
29Funding Capacity Expands
- Leading to Overall Value equalling Z3
(1-P)(V-Z2) Z2, and so on, so that as - The number of sub-periods N goes to its limit of
infinity, the maximal and safe debt funding level
Bo would approach - The Asset Value Ao V1 - P(N)(N1)
- Result related to Geanakoplos (2003).
30To Equal Full Asset Value
- As the number of periods until Maturity
Increases, PROVIDED that sufficient equity
capital is available, to Take Up Slack when the
bad state S1 continues - It is, of course, precisely such a lack of new
equity capital injection, arising from past
losses as A decreases, as well as Institutional
Behavior, that needs study
31Implications for SPV Capital?
- In the funding sequence derived above, the
sequences of debt, equity and total asset (A)
values before maturity satisfy - B1V(1-P) B2V(1-P) B3V(1-P2)
- E10 E2VP(1-P) E3VP2(1-P) ..
- A1V(1-P) A2V(1-P2) A3(1-P3) ..
- Limiting to the Initial Values at time 0 of
32With Infinite Debt Sequence of
- Ao V1-P(N)(N1) Bo V1-P(N)N Eo
VP(N)N(1-P(N)), and in the limit - As N tends to infinity, and P(N) to One, Credit
Risk P 1-Ao/V P(N)(N1) - Hence, to keep this chain of financing with
Equity Injections and Riskfree Debt going until
penultimate period, Expected
33Debt and Equity Injections
- Sum total of lost equity injections equals
- T VNP(N)(N1)1-P(N) which is the
Minimum Equity needed per asset, given
independent risks across many - Since LN(P) Limit of (N1)LNP(N) and, as
P(N) tends to 1 from below then LNP(N) P(N)
- 1, hence we obtain
34Equity Commitment Required
- T VP- LN(P), where P(1 - Ao/V) measures
the (initial) credit default risk, - Relative to the Maximal Payoff of Asset
- When P is SMALL, say Ao/V .95 after a small
regime shift from an Optimistic Scenario with Q
1 and Ao V, Note - T/V PLN(1/P) gtgt P same for T/Ao
35Can Far Exceed Magnitude of
- Long Run Default Risk of Funded Asset
- Note that Limit T(P) as P tends to zero is
indeed zero, employing LHospitals Rule the
more economically meaningful - T(P)/Ao P-LN(P)/(1-P) always has a
strictly positive derivative w.r.t. P - Plus, P ltT(P)/Aolt1 for all P in (0, 1)
36Bolton, Santos, Scheinkman
- Build Model combining Liquidity Shocks with
subsequent Adverse Selection due to private
information accruing to owner of risky asset who
seek interim liquidity - Two groups of investors, less and more patient,
with former having access to a technology having
high expected return - Coupled with above timing uncertainty
37Multiple (REE) Equilibrium
- Involving trading by the liquidity-seeking
impatient asset owners at different time points
pre- or post-resolution of private information
about future asset returns - Surprisingly, delayed trading equilibrium when it
exists, is ex ante Pareto Better it leads to
more investment by impatient agents in illiquid
risky asset, less cash
38Inside vs Outside Liquidity
- In essence, greater recourse to Outside Liquidity
in Delayed Trading equilibrium, leads to More
Gains from Trade among patient and impatient
agents, and hence greater ex ante expected social
surplus, despite adverse selection in asset price - HOWEVER, they ignore Problems such as Interim
Runs, within Impatient Banks
39Bhattacharya and Nyborg
- Look at Optimal Bank Bailout Schemes which Seek
to Remove Debt Overhang in Banks (in worse future
states) that impede additional investments by
them - In the face of Private Information about
Distribution of their Future Asset Values and,
the Option Values of Their Equities - While Minimizing Government Subsidy
40Asset Buyout vs New Capital
- If (size adjusted) Supports/Ranges, but Not
Likelihoods of Future Returns Same across Banks,
These Two Alternatives are Equivalent, and Either
Measure can Recapitalize Banks with Subsidy Equal
to their Outside (Equity) Option Values - If NOT, and Worse Quality Banks also Have Lower
Worst-case future returns
41MENUS Using Both Better
- We need to have Menu of Bailout Tools, and
heterogeneous Banks self-selecting - Ex1 Banks Future Payoffs 120. or 90, with
Likelihoods 1/2, 1/2 and 2/3, 1/3 and Debt
Due of 100. Either Buy 1/3 of Assets for 40 OR
Take 1/3 Equity for 10 - Ex 2 (Menu) Bad Bank Payoffs 120, or 80 1/2
Equity for 40/3, Assets for 110
42Proposal S. Bhattacharya, LSE
- Dynamic Credit Risk Transfer, and Financial
Stability Collaborators - Prof John Geanakoplos, Yale, USA
- Prof Kjell Nyborg, NHH, Norway
43Main Issues to be Addressed
- Impact of CRT on Monitoring Incentives of Loan
Originators, in Varying Macro States - Secondary Market Trading of CRT Assets
- Liquidity Shocks and Provision at Banks
- Adverse Selection Effects, and Cycles, in Trading
Liquidity Sharing among Banks - Resulting Shock Propagation Mechanisms
44A CRT Monitoring (Chiesa)
- Unlike most authors -- see the Duffie (2007)
survey -- who judge CRT to be harmful for the
originating banks monitoring incentives - Chiesa (2007) considers a set up in which
Monitoring is Unimportant in a Good state,
leading to (say) zero proportion of defaults, but
it Matters in Bad states, in which default is by
say 2 with 5 without monitoring
45Violation of MLRP and CRT
- Hence, with agents having SYMMETRIC beliefs on
underlying states, realisation of 2, rather than
0, default is indicative of bank monitoring
Rewarding Bank Insiders, as much as feasible,
THEN is thus Optimal - This is achieved by CRT, in the format of Selling
the Most Toxic Tranch of payoff to arise from 0
over 2 defaults, to Market
46But, What if Monitoring Matters
- Also in Good States, in which without it the
default rate would be 2 instead of 0, so CRT is
harmful for banks monitoring given good states,
in which 0 default signals it? - Further, suppose Bank Insiders who provide costly
monitoring Effort obtain Asymmetric information
regarding realised state a period in advance,
before choosing CRT level offer
47Partial Transfers of Toxic Tails
- Would now be optimal, indeed None IF the bank
insiders obtain Perfect Information on the
realised local macro state Good vs Bad! - In Dynamic contexts, with Markovian shifts across
Good and Bad states, would Market Equilibrium
Yield a Constrained Optimum? - If Not, especially with higher size preferred,
When would Sub-optimal monitoring arise?
48Giving Rise to Debt-Deflation
- Cycles even Without Irrational Exuberance?
- Arising from sub-optimal monitoring, hence
third-best loss of bank capital in Good states
making for Sub-optimal bank Capital levels, and
THUS lending volume, in Bad states to follow
inexorably, modulo serial correlation - Is there a Role for Bank Capital Regulation,
above level required for ex ante incentives?
49B. Liquidity Shocks and Adverse Selection in
Inter-Bank Markets
- Focus on ex ante inefficiencies in portfolio
choices of banks, e.g., Bhattacharya Gale
(1987), Bhattacharya, Goodhart, Sunirand,
Tsomocos (Economic Theory, 2007), with - Adverse Selection ex interim in Inter-Bank Loan
cum Liquidity Provision Markets, and - The impact of Securitization cum Tranching of
bank-originated loans on these processes
50CRT as Diversification Versus
- Net Transfer of the overall Banking System Loan
Default Risks to Other Market Agents - Empirically Gross CRT position holdings of banks
Dwarfs Net position, summed across them, by
factor of seven to eight Duffie 07 - However, with Demandable Deposits access to net
outside transfer of bank loan portfolio risks
matters in low aggregate liquidity state
51Efficient Contingent Risk Transfers to Non-Bank
Players
- This channel is emphasised in the work of Diamond
and Rajan (J of Finance, 2005) in which non-bank
investors are banks Lucky borrowers themselves
Bank Runs Imperil Their interim Ability to
subsequently Invest - Is CRT, Requiring Tranching to cope with adverse
selection (Demarzo and Duffie), an - efficient Mode of interbank Diversification?
52Non-Bank Investors and DPM
- Other Non-Bank Participants in CRT assets are
Funds, very often managed by delegated Portfolio
Managers with incentive contracts - Can Processes of Herding, arising from say
Reputational Concerns (Dasgupta and Prat, - Theoretical Economics, 2006) contribute to
explaining extent of liquidity withdrawal in
53Inter-bank CRT Markets when
- Liquidity Shocks may be Confounded with
fundamental Solvency Shocks for a subset? Witness
the massive lowering of their loan-deposit ratios
by US Banks overall in 30s! - Analogously, sharply differing flights to
liquidity cum safety by banks, as opposed to
security market participants, in ASEAN economies,
during 1997-98 flow reversals