|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Problem 7.10  Arthur Doyle at Baker Street | 
| Arthur Doyle is a currency trader for Baker Street, a private investment house in London. Baker Street’s clients are a collection of wealthy private investors who, with a minimum stake of £250,000 each, wish to speculate on the movement of currencies. The investors expect annual returns in excess of 25%. Although officed in London, all accounts and expectations are based in U.S. dollars. | 
| Arthur is convinced that the British pound will slide significantly — possibly to |  |  | $1.32 | 00
/£ — in the coming 
 |  | 30 |  to 
 |  |  |  |  | 60 |  days
. The current spot rate is 
$1.4260 | /£. Arthur wishes to buy a put on pounds which will yield the 25% return expected by his investors. Which of the following put options would you recommend he purchase. Prove your choice is the preferable combination of strike price, maturity, and up-front premium expense.
| Strike Price | Maturity | Premium | 
|  |  |  | $1.36 | /£
 |  | 30 days |  | $0.00081 | /£
|  |  |  | $1.34 | /£
		30 days		
 | $0.00021 | /£
|  | $1.32/£ | 		30 days		
 | $0.00004 | /£
		$1.36/£		60 days		
|  | $0.0033 | 3/£
		$1.34/£		60 days		
|  | $0.0015 | 0/£
		$1.32/£		60 days		
|  | $0.0006 | 0/£
| Assumptions | Values | 
| Current spot rate (US$/£) | 		$1.4260
| Expected endings spot rate in 30 to 60 days (US$/£) | 		$1.3200
| Potential investment principal per person (£) | £250,000.00 | 
|  | Put options on pounds | Put #1 | Put #2 | Put #3 | 
|  |  | Strike price |  (US$/£)
		$1.36		$1.34		$1.32
|  | Maturity (days) | 		30		30		30
|  | Premium (US$/£) | 		$0.00081		$0.00021		$0.00004
		Put options on pounds		
|  | Put #4 |  | Put #5 |  | Put #6 | 
		Strike price (US$/£)		$1.36		$1.34		$1.32
		Maturity (days)		60		60		60
		Premium (US$/£)		$0.0033		$0.0015		$0.0006
| Issues for Sydney to consider: | 
| 1.  Because his expectation is for “30 to 60 days” he should confine his choices to the 60 day options to be sure and capture | 
| the timing of the exchange rate change. (We have no explicit idea of why he believes this specific timing.) | 
| 2.  The choice of which strike price is an interesting debate. | 
| *  The lower the strike price (1.34 or 1.32), the cheaper the option price. | 
| *  The reason they are cheaper is that, statistically speaking, they are increasingly less likely to end up in the money. | 
| *  The choice, given that all the options are relatively “cheap,” is to pick the strike price which will yield the required return. | 
| *  The $1.32 strike price is too far ‘down,’ given that Sydney only expects the pound to fall to about $1.32. | 
				Put #4		Put #5		Put #6
|  |  | Net profit | 		Net profit		Net profit
		Strike price		
| $1.36000 | $1.34000 | $1.32000 | 
| Less expected spot rate |  |  | (1.32000) | 		(1.32000)		(1.32000)
| Less premium | 
| Profit | 
| If Sydney invested an individual’s principal purely | 
| in this specific option, they would purchase an | 
| option of the following notional principal (£): | 
| Expected profit, in total (profit rate x notional): | 
| Initial investment at current spot rate | 
| Return on Investment (ROI) | 
| Risk: They could lose it all (full premium) |