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CHAPTER 27 Managing Risk

767

example, if the yield on five-year Treasury notes is 5.25 percent, the swap spread is

.75 percent.25

The first payment on the swap occurs at the end of year 1 and is based on the starting LIBOR rate of 5 percent.26 The dealer (who pays floating) owes the bank 5 percent of $66.67 million, while the bank (which pays fixed) owes the dealer $4 million (6 percent of $66.67 million). The bank therefore makes a net payment to the dealer of 4 1.05 66.67 2 $.67 million:

 

Bank

 

 

.05 $66.67 $3.33

 

 

 

Counterparty

 

 

 

 

 

Bank

 

 

$4

 

 

 

Counterparty

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bank

 

 

 

Net $.67

 

 

 

Counterparty

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The second payment is based on LIBOR at year 1. Suppose it increases to 6 percent. Then the net payment is zero:

 

Bank

 

 

.06 $66.67 $4

 

 

 

Counterparty

 

 

 

 

 

Bank

 

 

$4

 

 

 

Counterparty

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bank

 

 

 

Net 0

 

 

 

Counterparty

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The third payment depends on LIBOR at year 2, and so on.

Notice that, when the two counterparties entered into the swap, the deal was fairly valued. In other words, the net cash flows had zero present value. What happens to the value of the swap as time passes? That depends on long-term interest rates. For example, suppose that after two years interest rates are unchanged, so a 6 percent note issued by the bank would continue to trade at its face value. In this case the swap still has zero value. (You can confirm this by checking that the NPV of a new three-year homemade swap is zero.) But if long rates increase over the two years to 7 percent (say), the value of a three-year note falls to

PV

4

 

4

 

4 66.67

$64.92 million

1.07

11.07 22

11.07 23

Now the fixed payments that the bank has agreed to make are less valuable and the swap is worth 66.67 64.92 $1.75 million.

How do we know the swap is worth $1.75 million? Consider the following strategy:

1.The bank can enter a new three-year swap deal in which it agrees to pay LIBOR on the same notional principal of $66.67 million.

2.In return it receives fixed payments at the new 7 percent interest rate, that is, .07 66.67 $4.67 per year.

The new swap cancels the cash flows of the old one, but it generates an extra. $.67 million for three years. This extra cash flow is worth

3 .67

PV ta1 11.07 2t $1.75 million

25Swap spreads fluctuate. After Russia defaulted on its debt in 1998 and the U.S. hedge fund Long Term Capital Management (LTCM) came close to collapse, five-year swap spreads nearly doubled from 0.5 percent to 0.8 percent.

26More commonly, interest rate swaps are based on three-month LIBOR and involve quarterly cash payments.

768

PART VIII Risk Management

Remember, ordinary interest rate swaps have no initial cost or value 1NPV 0), but their value drifts away from zero as time passes and long-term interest rates change. One counterparty wins as the other loses.

In our example, the swap dealer loses from the rise in interest rates. Dealers will try to hedge the risk of interest rate movements by engaging in a series of futures or forward contracts or by entering into an offsetting swap with a third party. As long as Friendly Bancorp and the other counterparty honor their promises, the dealer is fully protected against risk. The recurring nightmare for swap managers is that one party will default, leaving the dealer with a large unmatched position. This is called counterparty risk.

Currency Swaps

We now look briefly at an example of a currency swap.

Suppose that the Possum Company needs 11 million euros to help finance its European operations. We assume that the euro interest rate is about 5 percent, whereas the dollar rate is about 6 percent. Since Possum is better known in the United States, the financial manager decides not to borrow euros directly. Instead, the company issues $10 million of five-year 6 percent notes in the United States. Then it arranges with a counterparty to swap this dollar loan into euros. Under this arrangement the counterparty agrees to pay Possum sufficient dollars to service its dollar loan, and in exchange Possum agrees to make a series of annual payments in euros to the counterparty.

Here are Possum’s cash flows (in millions):

 

 

 

Year 0

 

 

 

Years 1– 4

 

Year 5

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Dollars

Euros

Dollars

Euros

Dollars

Euros

 

 

 

 

 

 

 

 

 

1.

Issue dollar loan

10

 

 

.6

 

10.6

 

2.

Swap dollars for euros

10

11

 

.6

.55

10.6

11.55

3.

Net cash flow

0

11

 

0

.55

0

11.55

 

 

 

 

 

 

 

 

 

 

 

 

Look first at the cash flows in year 0. Possum receives $10 million from its issue of dollar notes, which it then pays over to the swap counterparty. In return the counterparty sends Possum a check for a11 million. (We assume that at current rates of exchange $10 million is worth a11 million.)

Now move to years 1 through 4. Possum needs to pay interest of 6 percent on its debt issue, which works out at .06 10 $.6 million. The swap counterparty agrees to provide Possum each year with sufficient cash to pay this interest and in return Possum makes an annual payment to the counterparty of 5 percent of a11 million, or a.55 million. Finally, in year 5 the swap counterparty pays Possum enough to make the final payment of interest and principal on its dollar notes ($10.6 million), while Possum pays the counterparty a11.55 million.

The combined effect of Possum’s two steps (line 3) is to convert a 6 percent dollar loan into a 5 percent euro loan. You can think of the cash flows for the swap (line 2) as a series of contracts to buy euros in years 1 through 5. In each of years 1 through 4 Possum agrees to purchase $.6 million at a cost of .5 million euros; in year 5 it agrees to buy $10.6 million at a cost of 11.55 million euros.27

27Usually in a currency swap the two parties make an initial payment to each other (i.e., Possum pays the bank $10 million and receives a11 million). However, this is not necessary and Possum might prefer to buy the a11 million from another bank.

CHAPTER 27 Managing Risk

769

Credit Derivatives

In recent years there has been considerable growth in the use of credit derivatives, which protect lenders against the risk that a borrower will default. For example, bank A may be reluctant to refuse a loan to a major customer (customer X) but may be concerned about the total size of its exposure to that customer. Bank A can go ahead with the loan, but use credit derivatives to shuffle off the risk to bank B.

The most common credit derivative is known as a default swap. It works as follows. Bank A promises to pay a fixed sum each year to B as long as company X has not defaulted on its debts. If X defaults, B compensates A for the loss, but otherwise pays nothing. Thus you can think of B as providing A with long-term insurance against default in return for an annual insurance premium.28

Banks that have a portfolio of loans may be more concerned with the possibility of widespread defaults than with the risk of a single loan. In principle, they could negotiate a default swap on each individual loan. In practice, it is generally simpler to enter into a portfolio default swap that provides protection on the entire loan portfolio.

2 7 . 5 H O W T O S E T U P A H E D G E

To hedge risk the firm buys one asset and sells an equal amount of another asset. For example, our farmer owned 100,000 bushels of wheat and sold 100,000 bushels of wheat futures. As long as the wheat that the farmer owns is identical to the wheat that he has promised to deliver, this strategy minimizes risk.

In practice the wheat that the farmer owns and the wheat that he sells in the futures markets are unlikely to be identical. For example, if he sells wheat futures on the Kansas City exchange, he agrees to deliver hard, red winter wheat in Kansas City in September. But perhaps he is growing northern spring wheat many miles from Kansas City; in this case the prices of the two wheats will not move exactly together.

Figure 27.2 shows how changes in the prices of the two types of wheat may have been related in the past. Notice two things about this figure. First, the scatter of points suggests that the price changes are imperfectly related. If so, it is not possible to construct a hedge that eliminates all risk. Some residual, or basis, risk will remain. Second, the slope of the fitted line shows that a 1 percent change in the price of Kansas wheat was on average associated with an .8 percent change in the price of the farmer’s wheat. Because the price of the farmer’s wheat is relatively insensitive to changes in Kansas prices, he needs to sell .8 100,000 bushels of wheat futures to minimize risk.

Let us generalize. Suppose that you already own an asset, A (e.g., wheat), and that you wish to hedge against changes in the value of A by making an offsetting sale of another asset, B (e.g., wheat futures). Suppose also that percentage changes in the value of A are related in the following way to percentage changes in the value of B:

Expected change

a a change in b

in value of A

value of B

28Another form of credit derivative is the credit option. In this case A would pay an up-front premium and B would assume the obligation to pay A in the event of X’s default.

770

PART VIII Risk Management

F I G U R E 2 7 . 2

Hypothetical plot of past changes in the price of the farmer’s wheat against changes in the price of Kansas City wheat futures. A 1 percent change in the futures price implies, on average, an

.8 percent change in the price of the farmer’s wheat.

percent

3

 

 

 

 

 

2

 

 

 

 

 

wheat,

 

 

 

 

 

1

 

 

 

 

 

farmer's

 

 

 

 

 

0

 

 

 

 

 

in

 

 

 

 

 

 

change

–1

 

 

 

 

 

 

 

 

 

 

 

Price

–2

 

 

 

 

 

–2

–1

0

1

2

3

 

Price change in wheat futures, percent

Delta ( ) measures the sensitivity of A to changes in the value of B. It is also equal to the hedge ratio—that is, the number of units of B which should be sold to hedge

the purchase of A. You minimize risk if you offset your position in A by the sale of delta units of B.29

The trick in setting up a hedge is to estimate the delta or hedge ratio. This often calls for a strong dose of judgment. For example, suppose that Antarctic Air would like to protect itself against a hike in oil prices. As the financial manager, you need to decide how much a rise in oil prices would affect firm value. Suppose the company spent $200 million on fuel last year. Other things equal, a 10 percent increase in the price of oil will cost the company an extra .1 200 $20 million. But perhaps you can partially offset the higher costs by higher ticket prices, in which case earnings will fall by less than $20 million. Or perhaps an oil price rise will lead to a slowdown in business activity and therefore lower passenger numbers. In that case earnings will decline by more than $20 million. Working out the likely effect on firm value is even more tricky, because that depends on whether the rise is likely to be permanent. Perhaps the price rise will induce an increase in production or encourage consumers to economize on energy usage.

Sometimes in such cases some history may help. For example, you could look at how firm value changed in the past as oil prices changed. In other cases it may be possible to call on a little theory to set up the hedge.

Using Theory to Set Up the Hedge: An Example

Potterton Leasing has just purchased some equipment and arranged to rent it out for $2 million a year over eight years. At an interest rate of 12 percent, Potterton’s rental income has a present value of $9.94 million:30

PV

2

 

 

2

 

2

$9.94 million

1.12

1

1.12 22

1

1.12 28

 

 

 

 

29Notice that A, the item that you wish to hedge, is the dependent variable. Delta measures the sensitivity of A to changes in B.

30We ignore taxes in this example.

CHAPTER 27 Managing Risk

771

Potterton proposes to finance the deal by issuing a package of $1.91 million of one-year debt and $8.03 million of six-year debt, each with a 12 percent coupon. Think of its new asset (the stream of rental income) and the new liability (the issue of debt) as a package. Does Potterton stand to gain or lose on this package if interest rates change?

To answer this question, it is helpful to go back to the concept of duration that we introduced in Chapter 24. Duration, you may remember, is the weightedaverage time to each cash flow. Duration is important because it is directly related to volatility. If two assets have the same duration, their prices will be equally affected by any change in interest rates. If we call the total value of Potterton’s rental income V, then the duration of Potterton’s rental income is calculated as follows:

Duration V1 3PV1C1 2 1 4 3PV1C2 2 2 4 3PV1C3 2 3 4

9.194 e c 1.212 1 d c 11.122 22 2 d … c 11.122 28 8 d f3.9 years

We can also calculate the duration of Potterton’s new liabilities. The duration of the 1-year debt is 1 year, and the duration of the 6-year debt is 4.6 years. The duration of the package of 1- and 6-year debt is a weighted average of the durations of the individual issues:

Duration of liability 11.91/9.94 2 duration of 1-year debt

18.03/9.94 2 duration of 6-year debt

1.192 1 2 1.808 4.6 2 3.9 years

Thus, both the asset (the lease) and the liability (the debt package) have a duration of 3.9 years. Therefore, both are affected equally by a change in interest rates. If rates rise, the present value of Potterton’s rental income will decline, but the value of its debt obligation will also decline by the same amount. By equalizing the duration of the asset and that of the liability, Potterton has immunized itself against any change in interest rates. It looks as if Potterton’s financial manager knows a thing or two about hedging.

When Potterton set up the hedge, it needed to find a package of loans that had a present value of $9.94 million and a duration of 3.9 years. Call the proportion of the proceeds raised by the six-year loan x and the proportion raised by the one-year loan 11 x 2. Then

Duration of 1x duration of 6-year loan 2 311 x 2 package

duration of 1-year loan 4

3.9years 1x 4.6 years 2 311 x 2 1 year 4 x .808

Since the package of loans must raise $9.94 million, Potterton needs to issue .808 9.94 $8.03 million of the six-year loan.

An important feature of this hedge is that it is dynamic. As interest rates change and time passes, the duration of Potterton’s asset may no longer be the same as that of its liability. Thus, to remain hedged against interest rate changes, Potterton must be prepared to keep adjusting the duration of its debt.

772

PART VIII Risk Management

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cash Flows ($ millions)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Year

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

2

3

4

5

6

7

8

 

 

 

 

 

 

 

 

 

 

 

Balance at start of year

9.94

9.13

8.23

7.22

6.08

4.81

3.39

1.79

 

Interest at 12%

1.19

1.10

.99

.87

.73

.58

.40

.21

 

Sinking fund payment

.81

.90

1.01

1.13

1.27

1.42

1.60

1.79

 

Interest plus sinking

 

 

 

 

 

 

 

 

 

 

fund payment

2.00

2.00

2.00

2.00

2.00

2.00

2.00

2.00

 

 

 

 

 

 

 

 

 

 

 

T A B L E 2 7 . 4

Potterton can hedge by issuing this sinking fund bond that pays out $2 million each year.

If Potterton is not disposed to follow this dynamic hedging strategy, it has an alternative. It can devise a debt issue whose cash flows exactly match the rental income from the lease. For example, suppose that it issues an eight-year sinking fund bond; the amount of the sinking fund is $810,000 in year 1, and the payment increases by 12 percent annually. Table 27.4 shows that the bond payments (interest plus sinking fund) are $2 million in each year.

Since the cash flows on the asset exactly match those on the liability, Potterton’s financial manager can now relax. Each year the manager simply collects the $2 million rental income and hands it to the bondholders. Whatever happens to interest rates, the firm is always perfectly hedged.

Why wouldn’t Potterton’s financial manager always prefer to construct matching assets and liabilities? One reason is that it may be relatively costly to devise a bond with a specially tailored pattern of cash flows. Another may be that Potterton is continually entering into new lease agreements and issuing new debt. In this case the manager can never relax; it may be simpler to keep the durations of the assets and liabilities equal than to maintain an exact match between the cash flows.

Options, Deltas, and Betas

Here’s another case where some theory can help you set up a hedge. In Chapter 20 we came across options. These give you the right, but not the obligation, to buy or sell an asset. Options are derivatives; their value depends only on what happens to the price of the underlying asset.

The option delta summarizes the link between the option and the asset. For example, if you own an option to buy a share of Walt Disney stock, the change in the value of your investment will be the same as it would be if you held delta shares of Disney.

Since the option price is tied to the asset price, options can be used for hedging. Thus, if you own an option to buy a share of Disney and at the same time you sell delta shares of Disney, any change in the value of your position in the stock will be exactly offset by the change in the value of your option position.31 In other words, you will be perfectly hedged—hedged, that is, for the next short period of time.

31We are assuming that you hold one option and hedge by selling shares. If you owned one share and wanted to hedge by selling options, you would need to sell 1/ options.

CHAPTER 27 Managing Risk

773

Option deltas change as the stock price changes and time passes. Therefore, optionbased hedges need to be adjusted frequently.

Options can be used to hedge commodities too. The miller could offset changes in the cost of future wheat purchases by buying call options on wheat (or on wheat futures). But this is not the simplest strategy if the miller is trying to lock in the future cost of wheat. She would have to check the option delta to determine how many options to buy, and she would have to keep track of changes in the option delta and reset the hedge as necessary.32

It’s the same for financial assets. Suppose you hold a well-diversified portfolio of stocks with a beta of 1.0 and near-perfect correlation with the market return. You want to lock in the portfolio’s value at year-end. You could accomplish this by selling call options on the index, but to maintain the hedge, the option position would have to be adjusted frequently. It’s simpler just to sell index futures maturing at year-end.

Speaking of betas . . . what if your portfolio has a beta of .60, not 1.0? Then your hedge will require 40 percent fewer index futures contracts. And since your low-beta portfolio is probably not perfectly correlated with the market, there will be some basis risk as well. In this context our old friend beta 1 2 and the hedge ratio 1 2 are one and the same. Remember, to hedge A with B, you need to know because

Expected change in value of A a 1change in value of B 2

When A is a stock or portfolio, and B is the market, we estimate beta from the same relationship:

Expected change in stock or portfolio value a 1change in market index 2

2 7 . 6 I S “ D E R I VAT I V E ” A F O U R - L E T T E R W O R D ?

Our earlier example of the farmer and miller showed how futures may be used to reduce business risk. However, if you were to copy the farmer and sell wheat futures without an offsetting holding of wheat, you would not be reducing risk: You would be speculating.

Speculators in search of large profits (and prepared to tolerate large losses) are attracted by the leverage that derivatives provide. By this we mean that it is not necessary to lay out much money up front and the profits or losses may be many times the initial outlay.33 “Speculation” has an ugly ring, but a successful derivatives market needs speculators who are prepared to take on risk and provide more cautious people like our farmer and miller with the protection they need. For example, if an excess of farmers wish to sell wheat futures, the price of futures will be forced down until enough speculators are tempted to buy in the hope of a profit. If there is a surplus of millers wishing to buy wheat futures, the reverse will happen. The price of wheat futures will be forced up until speculators are drawn in to sell.

Speculation may be necessary to a thriving derivatives market, but it can get companies into serious trouble. Finance in the News describes how the German metals

32Quiz: What is the miller’s position if she buys call options on wheat and simply holds them to maturity?

33For example, if you buy or sell forward, no money changes hands until the contract matures, though you may be required to put up margin to show that you can honor your commitment. This margin does not need to be cash; it can be in the form of safe securities.

F I N A N C E I N T H E N E W S

THE DEBACLE AT METALLGESELLSCHAFT

In January 1994 the German industrial giant

would sell for less than more distant ones. Unfor-

Metallgesellschaft shocked investors with news of

tunately, this is what occurred in 1993. In that year

huge losses in its U.S. oil subsidiary, MGRM. These

there was a glut of oil, the storage tanks were full,

losses, later estimated at over $1 billion, brought the

and nobody was prepared to pay extra to get their

firm to the brink of bankruptcy and it was saved only

hands on oil. The result was that MGRM was forced

by a $1.9 billion rescue package from 120 banks.

to pay a premium to roll over each stack of matur-

The previous year MGRM had embarked on what

ing contracts.

looked like a sure-fire way to make money. It offered

The fall in oil prices had another unfortunate

its customers forward contracts on deliveries of

consequence for MGRM. Futures contracts are

gasoline, heating oil, and diesel fuel for up to

marked to market. This means that the investor

10 years. These price guarantees proved extremely

settles up the profits and losses on each contract as

popular. By September 1993, MGRM had sold for-

they arise. Therefore, as oil prices continued to fall

ward over 150 million barrels of oil at prices that

in 1993, MGRM incurred losses on its purchases of

were $3 to $5 a barrel over the prevailing spot prices.

oil futures. This resulted in huge margin calls.* The

As long as oil prices did not rise appreciably,

offsetting good news was that the fall in oil prices

MGRM stood to make a handsome profit from its

meant that its long-term forward contracts were

forward sales, but if oil prices did return to their

looking increasingly profitable, but this profit was

level of earlier years the result would be a calami-

not money in the bank.

tous loss. MGRM therefore sought to avoid such an

When Metallgesellschaft’s board learned of

outcome by buying energy futures. Unfortunately,

these problems, it fired the chief executive and in-

the long-term futures contracts that were needed

structed the company to cease all hedging activi-

to offset MGRM’s price guarantees did not exist.

ties and to start negotiations with customers to

MGRM’s solution was to enter into what is known as

cancel the long-term contracts. Almost immedi-

a “stack-and-roll” hedge. In other words, it bought a

ately the fall in oil prices reversed. Within eight

stack of short-dated futures contracts and, as these

months the price had risen about 40 percent. If

were about to expire, it rolled them over into a fresh

only MGRM had been able to hold on, it would

stack of short-dated contracts.

have enjoyed a huge cash inflow.

MGRM was relaxed about the mismatch be-

Observers have continued to argue about the

tween the long-term maturity of its price guaran-

Metallgesellschaft debacle. Was the company’s

tees and the much shorter maturity of its futures

belief that the net convenience yield would re-

contracts. It could point to past history to justify its

main positive a reasonable assumption or a gi-

confidence, for in most years energy traders have

gantic speculation? How much did the company

placed a high value on owning the oil rather than

anticipate its cash needs and could it have fi-

having a promise of future delivery. In other words,

nanced them by borrowing on the strength of its

the net convenience yield on oil has generally been

long-term forward contracts? Did senior manage-

positive (see Figure 27.1). As long as that contin-

ment mistake the margin calls for losses and just

ued to be the case, then each time that MGRM

lose its nerve when it decided to liquidate the

rolled over its futures contracts, it would be selling

company’s positions?

its maturing contracts at a higher price than it

 

 

would need to pay for the stack of new contracts.

 

 

*In addition to buying futures contracts, MGRM also bought short-

However, if the net convenience yield were to be-

term over-the-counter forward contracts and commodity swaps. As

these matured, MGRM had to make good the loss on them, even

come negative, the maturing futures contracts

though it did not receive the gains on the price guarantees.

 

 

 

 

 

 

774

CHAPTER 27 Managing Risk

775

and oil trading company, Metallgesellschaft, took a $1 billion bath on its positions in oil futures. Metallgesellschaft had plenty of company. The Japanese company, Showa Shell, reported a loss of $1.5 billion on positions in foreign exchange futures. Another Japanese firm, Sumitomo Corporation, lost over $2 billion when a rogue trader tried to buy enough copper to control that market.34 And in 1995 Baring Brothers, a bluechip British merchant bank with a 200-year history, became insolvent. The reason: Nick Leeson, a trader in Baring’s Singapore office, had placed very large bets on the Japanese stock market index resulting in losses of $1.4 billion.

These tales of woe have some cautionary messages for corporations. During the 1970s and 1980s many firms turned their treasury operations into profit centers and proudly announced their profits from trading in financial instruments. But it is not possible to make large profits in financial markets without also taking large risks, so these profits should have served as a warning rather than a matter for congratulation.

A Boeing 747 weighs 400 tons, flies at nearly 600 miles per hour, and is inherently very dangerous. But we don’t ground 747s; we just take precautions to ensure that they are flown with care. Similarly, it is foolish to suggest that firms should ban the use of derivatives, but it makes obvious sense to take precautions against their misuse. Here are two bits of horse sense:

Precaution 1. Don’t be taken by surprise. By this we mean that senior management needs to monitor regularly the value of the firm’s derivatives positions and to know what bets the firm has placed. At its simplest, this might involve asking what would happen if interest rates or exchange rates were to change by 1 percent. But large banks and consultants have also developed sophisticated models for measuring the risk of derivatives positions. J. P. Morgan, for example, offers corporate clients its RiskMetrics software to keep track of their risk.

Precaution 2. Place bets only when you have some comparative advantage that ensures the odds are in your favor. If a bank were to announce that it was drilling for oil or launching a new soap powder, you would rightly be suspicious about whether it had what it takes to succeed. Conversely, when an industrial corporation places large bets on interest rates or exchange rates, it is competing against some highly paid pros in banks and other financial institutions. Unless it is better informed than they are about future interest rates or exchange rates, it should use derivatives for hedging, not for speculation.

Imprudent speculation in derivatives is undoubtedly an issue of concern for the company’s shareholders, but is it a matter for more general concern? Some people believe so. They point to the huge volume of trading in derivatives and argue that speculative losses could lead to major defaults that might threaten the whole financial system. These worries have led to calls for increased regulation of derivatives markets.

Now, this is not the place for a discussion of regulation, but we should warn you about careless measures of the size of the derivatives markets and the possible losses. In December 2000 the notional value of outstanding derivative contracts was about $110 trillion.35 This is a very large sum, but it tells you nothing about the

34The attempt failed, and the company later agreed to pay $150 million more in fines and restitution.

35Bank of International Settlements, Derivatives Statistics (www.bis.org/statistics/derstats.htm).

776

PART VIII Risk Management

money that was being put at risk. For example, suppose that a bank enters into a $10 million interest rate swap and the other party goes bankrupt the next day. How much has the bank lost? Nothing. It hasn’t paid anything up front; the two parties simply promised to pay sums to each other in the future. Now the deal is off.

Suppose that the other party does not go bankrupt until a year after the bank entered into the swap. In the meantime interest rates have moved in the bank’s favor, so it should be receiving more money from the swap than it is paying out. When the other side defaults on the deal, the bank loses the difference between the interest that it is due to receive and the interest that it should pay. But it doesn’t lose $10 million.36

The only meaningful measure of the potential loss from default is the amount that it would cost firms showing a profit to replace their swap positions. This figure is only a small fraction of the principal amount of swaps outstanding.37

36This does not mean that firms don’t worry about the possibility of default, and there are a variety of ways that they try to protect themselves. In the case of swaps, firms are reluctant to deal with banks that do not have the highest credit rating.

37United States General Accounting Office, “Financial Derivatives: Actions Needed to Protect the Financial System,” report to congressional requesters, May 1994. This does not mean that swaps have increased risk. If counterparties use swaps to hedge risk, they are less likely to default.

SUMMARY As a manager, you are paid to take risks, but you are not paid to take any risks. Some are simply bad bets, and others could jeopardize the success of the firm. In

these cases you should look for ways to insure or hedge.

Most businesses take out insurance against a variety of risks. Insurance compa-

nies have considerable expertise in assessing risk and may be able to pool risks by

holding a diversified portfolio. Insurance works less well when the insurance policy attracts only the worst risks (adverse selection) or when the insured firm is tempted to skip on maintenance and safety procedures (moral hazard).

Insurance is generally purchased from specialist insurance companies, but sometimes firms issue specialized securities instead. Cat (catastrophe) bonds are an example.

The idea behind hedging is straightforward. You find two closely related assets. You then buy one and sell the other in proportions that minimize the risk of your net position. If the assets are perfectly correlated, you can make the net position risk-free.

The trick is to find the hedge ratio or delta—that is, the number of units of one asset that is needed to offset changes in the value of the other asset. Sometimes the best solution is to look at how the prices of the two assets have moved together in the past. For example, suppose you observe that a 1 percent change in the value of B has been accompanied on average by a 2 percent change in the value of A. Then delta equals 2.0; to hedge each dollar invested in A, you need to sell two dollars of B.

On other occasions a little theory can help to set up the hedge. For example, the effect of a change in interest rates on an asset’s value depends on the asset’s duration. If two assets have the same duration, they will be equally affected by fluctuations in interest rates.

Many of the hedges described in this chapter are static. Once you have set up the hedge, you can take a long vacation, confident that the firm is well protected. However, some hedges, such as those that match durations, are dynamic. As time passes and prices change, you need to rebalance your position to maintain the hedge.

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