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FRM http:// pluto.mscc.huji.ac.i l/~mswiener/zvi.html HUJI-03 Zvi Wiener mswiener @ mscc . huji .ac. il 02-588-3049 Financial Risk Management

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Zvi Wiener VaR-PJorion-Ch1-3 slide 2

Financial Risk Management

Zvi Wiener

Head of Finance Department

The Hebrew University of Jerusalem

02-588-3049, [email protected]

Arik Perez

[email protected]

tel. 050-412-733, 02-531-7751

Zvi Wiener VaR-PJorion-Ch1-3 slide 3

Statistics

Random variables

Mean, Standard Deviation, Correlation

Normal distribution

BABA

BABABA 222222

Zvi Wiener VaR-PJorion-Ch1-3 slide 4

Basic Corporate Finance

NPV, IRR, YTM

Assets, Liabilities

Regulators, Bank of Israel, MOF

ISDA, SEC

Zvi Wiener VaR-PJorion-Ch1-3 slide 5

Investments

Stocks, Indices, , CAPM,

Bonds, duration, convexity NIS, CPI linked

callable, puttable, convertible

Forwards, Futures, Swaps

Options, European, American

Call, Put, BS formula

Markets: prices, volatilites, LIBORs, swap rates

FRMhttp://pluto.mscc.huji.ac.il/

~mswiener/zvi.htmlHUJI-03

Following P. Jorion, Value at Risk, McGraw-Hill

Chapter 1

The Need for Risk Management

Financial Risk Management

Zvi Wiener VaR-PJorion-Ch1-3 slide 7

Financial Risks

Risk is the volatility of unexpected outcomes.

Business Risk

Financial Risk

Legal Risk

Operational Risk

Zvi Wiener VaR-PJorion-Ch1-3 slide 8

Analytic Risk Management Tools

Duration 1938

Markowitz mean-variance 1952

Sharpe’s CAPM 1963

Multiple factor models 1966

Black-Merton-Scholes model 1973

RAROC 1983

Limits by duration buckets 1986

Zvi Wiener VaR-PJorion-Ch1-3 slide 9

Analytic Risk Management Tools

Risk-weighted assets (banks) 1988

Stress Testing 1992

Value-at-Risk, VaR 1993

RiskMetrics 1994

CreditMetrics 1997

Integration of credit and market 1998-

Enterprisewide RM 2000-

Zvi Wiener VaR-PJorion-Ch1-3 slide 10

Derivatives and Risk Management

Stocks and bonds are securities – issued to raise capital.

Derivatives are contracts, agreements used for risk transfer.

Zvi Wiener VaR-PJorion-Ch1-3 slide 11

Financial Derivatives

Futures, Forwards, Swaps

Options

European, American, Asian, Parisian

Call, Put

Cap, Floor

Credit derivatives

Zvi Wiener VaR-PJorion-Ch1-3 slide 12

Types of Financial Risks

Market Risk

Credit Risk

Liquidity Risk

Operational Risk

Legal Risk

Zvi Wiener VaR-PJorion-Ch1-3 slide 13

What is the current Risk?

duration, convexity

volatility

delta, gamma, vega

rating

target zone

Bonds

Stocks

Options

Credit

Forex

Total ?

Zvi Wiener VaR-PJorion-Ch1-3 slide 14

Standard Approach

Zvi Wiener VaR-PJorion-Ch1-3 slide 15

Modern Approach

Financial Institution

Zvi Wiener VaR-PJorion-Ch1-3 slide 16

Example

You live in Herzliya and work in Tel-Aviv.

When do you have to leave your home to be at work at 8:30?

Zvi Wiener VaR-PJorion-Ch1-3 slide 17

How much can we lose?

Everything

correct, but useless answer.

How much can we lose realistically?

Zvi Wiener VaR-PJorion-Ch1-3 slide 18

Definition

VaR is defined as the predicted worst-case

loss at a specific confidence level (e.g. 99%)

over a certain period of time.

Zvi Wiener VaR-PJorion-Ch1-3 slide 19

Definition (Jorion)

VaR is the worst loss over a target horizon

with a given level of confidence.

Zvi Wiener VaR-PJorion-Ch1-3 slide 20

-3 -2 -1 1 2 3

0.2

0.4

0.6

0.8

1

Profit/Loss

VaR

1% VaR1%

Zvi Wiener VaR-PJorion-Ch1-3 slide 21

Meaning of VaR

A portfolio manager has a daily VaR equal $1M at 99% confidence level.

This means that there is only one chance in 100 that a daily loss bigger than $1M occurs,

1%VaR

under normal market conditions.

Zvi Wiener VaR-PJorion-Ch1-3 slide 22

Returns

year

1% of worst cases

Zvi Wiener VaR-PJorion-Ch1-3 slide 23

Main Ideas

A few well known risk factors

Historical data + economic views

Diversification effects

Testability

Easy to communicate

Zvi Wiener VaR-PJorion-Ch1-3 slide 24

Conventional Analysis

Risk factor

$ value

sensitivity

scenarios

Zvi Wiener VaR-PJorion-Ch1-3 slide 25

VaR approach

Risk factor

$

yield

price

Zvi Wiener VaR-PJorion-Ch1-3 slide 26

Important

VaR is a necessary, but not sufficient procedure for controlling risk.

It must be supplemented by limits and controls, in addition to an independent risk-management function.

Sound risk-management practices.

FRMhttp://pluto.mscc.huji.ac.il/

~mswiener/zvi.htmlHUJI-03

Following P. Jorion, Value at Risk, McGraw-Hill

Chapter 2

Lessons from Financial Disasters

Financial Risk Management

Zvi Wiener VaR-PJorion-Ch1-3 slide 28

Derivatives 1993-1995

($ million)

Shova Shell, Japan 1,580

Kashima Oil, Japan 1,450

Metallgesellschaft 1,340

Barings, U.K. 1,330

Codelco, Chile 200

Procter & Gamble, US 157

Zvi Wiener VaR-PJorion-Ch1-3 slide 29

Public Funds

($ million)

Orange County 1,640

San Diego 357

West Virginia 279

Florida State Treasury 200

Cuyahoga County 137

Texas State 55

Zvi Wiener VaR-PJorion-Ch1-3 slide 30

Barings

February 26, 1995

233 year old bank

28 year old Nick Leeson

$1,300,000,000 loss

bought by ING for $1.5

Zvi Wiener VaR-PJorion-Ch1-3 slide 31

Metallgesellshaft

14th largest industrial group

58,000 employees

offered long term oil contracts

hedge by long-term forward contracts

short term contracts were used (rolling hedge)

1993 price fell from $20 to $15

$1B margin call in cash

Zvi Wiener VaR-PJorion-Ch1-3 slide 32

Orange County

Bob Citron, the county treasures

$7.5B portfolio (schools, cities)

borrowed $12.5B, invested in 5yr. notes

interest rates increased

reported at cost - big mistake!

realized loss of $1.64B

Zvi Wiener VaR-PJorion-Ch1-3 slide 33

Daiwa

12-th largest bank in Japan

September 1995

Hidden loss of $1.1B accumulated over 11 years

Toshihide Igushi, trader in New York

Had control of front and back offices

In 92 and 93 FED warned Daiwa about bad

management structure.

Zvi Wiener VaR-PJorion-Ch1-3 slide 34

Zvi Wiener VaR-PJorion-Ch1-3 slide 35

Big Losses

Bank Negara, Malaysia $3B 92

Banesto (Spain’s 5th bank) $4.7B 93

Credit Lyonnais $15B 94

S&L short deposits, long loans $150 80s

Japan $550 90s

Zvi Wiener VaR-PJorion-Ch1-3 slide 36

ResponsesG-30 reportDPG = Derivatives Policy Group, risk.ifci.ch

JPMorgan’s RiskMetrics www.riskmetrics.com

GARP www.garp.com PRMIA www.prmia.org

GAO = General Accounting Office, www.gao.gov/reports.htm

FASB FAS 133 www.fas133.com, FAS 107

IASC, IAS 39 www.iasc.org.uk

SEC = Securities and Exchange Commission

www.sec.gov/rules/final/33-7386.txt

FRMhttp://pluto.mscc.huji.ac.il/

~mswiener/zvi.htmlHUJI-03

Following P. Jorion, Value at Risk, McGraw-Hill

Chapter 3

Regulatory Capital Standards with VaR

Financial Risk Management

Zvi Wiener VaR-PJorion-Ch1-3 slide 38

Why regulation?

Externalities

Deposit insurance

Moral hazard – less incentives to control risk

Basel Accord 1988

measure of solvency = Cooke ratio

Zvi Wiener VaR-PJorion-Ch1-3 slide 39

Cooke ratio

The Basel Accord requires capital to be at least 8% of the total risk-weighted assets of the bank.

Capital definition is broad:

Tier 1. Stocks, reserves (retained earnings) ( 50%)

Tier 2. Perpetual securities, undisclosed reserves, subordinated debt >5 years.

Zvi Wiener VaR-PJorion-Ch1-3 slide 40

Weights Asset Type

0% CashClaims on OECD central governmentlocal currency claims on central banks

20% Cash to be receivedOECD banks and regulated securities firmsnon-OECD banks below 1 yearmultilateral development banksforeign OECD public sector entities

50% residential mortgage loans

Zvi Wiener VaR-PJorion-Ch1-3 slide 41

Weights Asset Type

100% Claims on private sector (corp. debt, equity…)Claims on non-OECD banks above 1 yearReal estatePlant and equipment

At national discretion0-50% Claims on domestic OECD public-sector entities

OECD (Organization for Economic Cooperation and Development): Austria, Belgium, Canada, Denmark, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, The Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, Turkey, UK, Japan, Finland, Australia, New Zealand, Mexico, Czech Republic, Hungary, Korea and Poland.

Zvi Wiener VaR-PJorion-Ch1-3 slide 42

Credit Risk Charge

iii assetwCRC %8

Zvi Wiener VaR-PJorion-Ch1-3 slide 43

Activity Restrictions

Restrictions on large risks (over 10% of capital)

must be reported

over 25% prohibited

total of large risks can not exceed 8*capital

Zvi Wiener VaR-PJorion-Ch1-3 slide 44

Criticism of 1988 Approach

Regulatory arbitrage (securitization)

Credit derivatives

Inadequate differentiation of credit risks

Non-recognition of term structure effect

Non-recognition of risk mitigation

Non-recognition of diversification

Non-recognition of market risk

Zvi Wiener VaR-PJorion-Ch1-3 slide 45

Market Risk Amendment 1996

Trading book – financial instruments that intentionally held for short-term resale and are typically marked-to-market

Banking book – other instruments, like loans.

TRC = CRC + MRC

Tier 3 capital: short-term subordinated debt (must be less than 2.5*Tier1)

Zvi Wiener VaR-PJorion-Ch1-3 slide 46

The Standardized Model

Maturity bands

Partial netting

Duration weights

No diversification across risks

Zvi Wiener VaR-PJorion-Ch1-3 slide 47

The Internal Models Approach

Quantitative parameters for VaR10 business days or 2 weeks

99% confidence level

at least one year of historical data updated at least quarterly

Treatment of correlations – can be recognized

Zvi Wiener VaR-PJorion-Ch1-3 slide 48

1 day can be scaled by square root of 10

Typically average times k is used.

k initially is set to 3, but later it can be increased

Specific Risk Charge SRC is added.

ti

titt SRCVaRVaRk

MaxMRC

60

11,

60

Zvi Wiener VaR-PJorion-Ch1-3 slide 49

Basel Rules MRC

Market Risk Charge = MRC

SRC - specific risk charge, k 3.

tti

itt SRCVaRVaRk

MaxMRC

1

60

1

,60

10%)99,1( dVaRVaR tt

Zvi Wiener VaR-PJorion-Ch1-3 slide 50

Backtesting

Verification of Risk Management models.

Comparison if the model’s forecast VaR with

the actual outcome - P&L.

Exception occurs when actual loss exceeds

VaR.After exception - explanation and action.

Zvi Wiener VaR-PJorion-Ch1-3 slide 51

Stress

Designed to estimate potential losses in abnormal markets.

Extreme events

Fat tails

Central questions:

How much we can lose in a certain scenario?

What event could cause a big loss?

Zvi Wiener VaR-PJorion-Ch1-3 slide 52

Further development

Basel II

Better treatment of credit risk

Operational risk

Zvi Wiener VaR-PJorion-Ch1-3 slide 53

Non banks

Securities Firms

Insurance companies

Pension funds

SEC reporting 7A in 10K

בארץ – ועדת גלאי – דיווח איכותי, אחר כך כמותי

Zvi Wiener VaR-PJorion-Ch1-3 slide 54

FRM-99, Question 89

What is the correct interpretation of a $3 overnight VaR figure with 99% confidence level?

A. expect to lose at most $3 in 1 out of next 100 days

B. expect to lose at least $3 in 95 out of next 100 days

C. expect to lose at least $3 in 1 out of next 100 days

D. expect to lose at most $6 in 2 out of next 100 days

Zvi Wiener VaR-PJorion-Ch1-3 slide 55

FRM-99, Question 89

What is the correct interpretation of a $3 overnight VaR figure with 99% confidence level?

A. expect to lose at most $3 in 1 out of next 100 days

B. expect to lose at least $3 in 95 out of next 100 days

C. expect to lose at least $3 in 1 out of next 100 days

D. expect to lose at most $6 in 2 out of next 100 days

Zvi Wiener VaR-PJorion-Ch1-3 slide 56

Properties of Risk Measure

Monotonicity (X<Y, R(X)>R(Y))

Translation invariance R(X+k) = R(X)-k

Homogeneity R(aX) = a R(X) (liquidity??)

Subadditivity R(X+Y) R(X) + R(Y)

the last property is violated by VaR!

Zvi Wiener VaR-PJorion-Ch1-3 slide 57

No subadditivity of VaR

Bond has a face value of $100,000, during the target period there is a probability of 0.75% that there will be a default (loss of $100,000).

Note that VaR99% = 0 in this case.

What is VaR99% of a position consisting of 2

independent bonds?

Zvi Wiener VaR-PJorion-Ch1-3 slide 58

FRM-98, Question 22

Consider arbitrary portfolios A and B and their combined portfolio C. Which of the following relationships always holds for VaRs of A, B, and C?

A. VaRA+ VaRB = VaRC

B. VaRA+ VaRB VaRC

C. VaRA+ VaRB VaRC

D. None of the above

Zvi Wiener VaR-PJorion-Ch1-3 slide 59

FRM-98, Question 22

Consider arbitrary portfolios A and B and their combined portfolio C. Which of the following relationships always holds for VaRs of A, B, and C?

A. VaRA+ VaRB = VaRC

B. VaRA+ VaRB VaRC

C. VaRA+ VaRB VaRC

D. None of the above

Zvi Wiener VaR-PJorion-Ch1-3 slide 60

Confidence level

low confidence leads to an imprecise result.

For example 99.99% and 10 business days will require history of

100*100*10 = 100,000 days in order to have only 1 point.

Zvi Wiener VaR-PJorion-Ch1-3 slide 61

Time horizon

long time horizon can lead to an imprecise result.

1% - 10 days means that we will see such a loss approximately once in 100*10 = 3 years.

5% and 1 day horizon means once in a month.

Various subportfolios may require various horizons.

Zvi Wiener VaR-PJorion-Ch1-3 slide 62

Time horizon

When the distribution is stable one can translate VaR

over different time periods.

TdayVaRdaysTVaR )1()(

This formula is valid (in particular) for iid

normally distributed returns.

Zvi Wiener VaR-PJorion-Ch1-3 slide 63

FRM-97, Question 7

To convert VaR from a one day holding period to a ten day holding period the VaR number is generally multiplied by:

A. 2.33

B. 3.16

C. 7.25

D. 10

Zvi Wiener VaR-PJorion-Ch1-3 slide 64

FRM-97, Question 7

To convert VaR from a one day holding period to a ten day holding period the VaR number is generally multiplied by:

A. 2.33

B. 3.16

C. 7.25

D. 10

Zvi Wiener VaR-PJorion-Ch1-3 slide 65

Home assignment

Read chapters 1-3, pay attention to boxes.

Zvi Wiener VaR-PJorion-Ch1-3 slide 66

The end