© 2004 South-Western Publishing 1 Chapter 9 Stock Index Futures

2 Outline Stock indexes and their futures contracts Uses of stock index futures Hedging with stock index futures

3 Capitalization-Weighted Indexes The S&P 500 index is capitalization- weighted – Each of the 500 share prices in the index is multiplied by the number of outstanding shares in that particular firm – Standard and Poor’s calculates the index by adding these figures and dividing by the index divisor

4 Capitalization-Weighted Indexes (cont’d) Assume only three firms are in an index Assume the initial divisor is arbitrarily set at 2,700,000

5 Capitalization-Weighted Indexes (cont’d) Day 1 Index = 270,000,000/2,700,000 = StockShares OutClosing PriceShares x Price A1,000,000$1010,000,000 B5,000,000$22110,000,000 C10,000,000$15150,000,000 Total270,000,000

6 Capitalization-Weighted Indexes (cont’d) Day 2 Index = 271,000,000/2,700,000 = StockShares OutClosing PriceShares x Price A1,000,000$1111,000,000 B5,000,000$20100,000,000 C10,000,000$16160,000,000 Total271,000,000

7 Capitalization-Weighted Indexes (cont’d) Day 3 – B splits two for one Index = 262,000,000/2,700,000 = StockShares OutClosing PriceShares x Price A1,000,000$1212,000,000 B10,000,000$11110,000,000 C10,000,000$14140,000,000 Total262,000,000

8 Stock Index Futures Contracts As with other futures, a stock index future is a promise to: – Buy or sell – Standardized units – Of a specific index – At a fixed price – At a predetermined future date

9 Stock Index Futures Contracts (cont’d) Stock index futures are similar in every respect to a traditional agricultural contract except for the matter of delivery – Index futures settle in cash rather than by delivery of the underlying asset – You actually deliver the dollar difference between the original trade price and the final price of the index at contract termination

10 Elements Affecting the Price of A Futures Contract S&P 500 Stock Index Futures SPX Index T-bill Rate Time until Settlement SPX Dividend Yield

11 Elements Affecting the Price of A Futures Contract (cont’d) Stocks pay dividends, while futures do not pay dividends – Shows up as a price differential in the futures price/underlying asset relationship Stocks do not accrue interest Posting margin for futures results in interest – Shows up as a price differential in the futures price/underlying asset relationship

12 Determining the Fair Value of A Futures Contract The futures price should equal the index plus a differential based on the short-term interest rate minus the dividend yield:

13 Determining the Fair Value of A Futures Contract (cont’d) Calculating the Fair Value of A Futures Contract Example Assume the following information for an S&P 500 futures contract:  Current level of the cash index (S) = 1,  T-bill yield ® = 6.07%  S&P 500 dividend yield (D) = 1.10%  Days until December settlement (T) = 121 = 0.33 years

14 Determining the Fair Value of A Futures Contract (cont’d) Calculating the Fair Value of A Futures Contract Example The fair value of the S&P 500 futures contract is:

15 Synthetic Index Portfolios Large institutional investors can replicate a well-diversified portfolio of common stock by holding – A long position in the stock index futures contract and – Satisfying the margin requirement with T-bills The resulting portfolio is a synthetic index portfolio

16 Synthetic Index Portfolios (cont’d) The futures approach has the following advantages over the purchase of individual stocks: – Transaction costs will be much lower on the futures contracts – The portfolio will be much easier to follow and manage

17 Basic Convergence As time passes, the difference between the cash index and the futures price will narrow – At the end of the futures contract, the futures price will equal the index (basic convergence)

18 Uses of Stock Index Futures Speculation Spreading Arbitrage Anticipation of stock purchase or sale Hedging

19 Speculation Each one-point movement in the S&P 500 index translates to $250 – A person who is bullish could obtain substantial leverage by buying S&P contracts

20 Spreading Spreads using index futures can be used to speculate with reduced risk – E.g., a speculator believing the Nasdaq will outperform the Dow Jones could employ an intermarket spread by buying Nasdaq 100 futures and selling DJIA futures

21 Arbitrage Sometimes the market price of a futures contract temporarily deviates from the price predicted by pricing theory – An arbitrageur could short the futures contracts and buy stock if the price deviates upward – An arbitrageur could short the stock and buy futures contracts if the price deviates downward

22 Anticipation of Stock Purchase or Sale Futures contracts can be used to lock in a price in anticipation of a stock purchase or sale – E.g., a portfolio manager might want to get out of the market, but for tax reasons does not want to sell securities until the new year

23 Hedging The primary purpose of S&P futures is to facilitate risk transfer from one who bears undesired risk to someone else willing to bear the risk – S&P futures are used by most large commercial banks and by many pension funds and foundations to hedge

24 Systematic and Unsystematic Risk Systematic factors are those that influence the stock market as a whole – E.g., interest rates, economic indicators, political climate, etc. Unsystematic factors are unique to a specific company or industry – E.g., earnings reports, technological developments, labor negotiations, etc.

25 Systematic and Unsystematic Risk (cont’d) Proper portfolio diversification can virtually eliminate unsystematic risk The market assumes that you have been smart enough to reduce risk through diversification – Beta measures the relative riskiness of a portfolio compared to a benchmark portfolio like the S&P 500

26 Systematic and Unsystematic Risk (cont’d) Portfolio Variance Number of Securities

27 Introduction To construct a proper hedge, you must realize that portfolios are of – Different sizes – Different risk levels The hedge ratio incorporates the relative value of the stock and futures, and accounts for the relative riskiness of the two portfolios

28 Introduction (cont’d) To determine the hedge ratio, you need: – The value of the chosen futures contract – The dollar value of the portfolio to be hedged – The beta of the portfolio

29 Introduction (cont’d) Determining the Factors for A Hedge Suppose the manager of a $75 million stock portfolio (with a beta of 0.9 and a dividend yield of 1.0%) wants to hedge using the December S&P 500 futures. On the previous day, the S&P 500 closed at 1,484.43, and the DEC 00 S&P 500 futures closed at 1,

30 Introduction (cont’d) Determining the Factors for A Hedge (cont’d) The value of the futures contract is: $250 x 1, = $379,300

31 Introduction (cont’d) Determining the Factors for A Hedge (cont’d) The hedge ratio is:

32 Hedging in Retrospect A hedge will usually not be perfect because: – It is not possible to hedge exactly – Stock portfolios seldom behave exactly as their beta suggests – The futures price does not move in lockstep with the underlying index (basis risk) – The dividends on the S&P 500 index do not occur uniformly over time

33 Adjusting Market Risk Futures can be used to adjust the level of market risk in a portfolio:

34 Adjusting Market Risk (cont’d) Determining the Number of Contracts Needed to Increase Market Exposure Suppose the manager of a $75 million stock portfolio with a beta of 0.9 would like to increase market exposure by increasing beta to 1.5. Yesterday, DEC 00 S&P 500 futures closed at How can the manager use futures to accomplish this goal, assuming the composition of the stock portfolio remains unchanged?

35 Adjusting Market Risk (cont’d) Determining the Number of Contracts Needed to Increase Market Exposure (cont’d) The manager should go long futures and hold them with the stock portfolio. Specifically, he should purchase 119 S&P 500 futures contracts: