Wednesday, 13 February 2008

Analysis of Warrant Data (Part 6)

Time really flies. Today is the 7th day of Chinese Lunar New Year also known as 人日, which means it is the birthday of human beings. Therefore, I would like to wish everyone a happy birthday. This is part 6 of my posting on Analysis of Warrant Data. In this post I will talk about effective gearing and gearing.

The biggest appeal of warrant trading lies in the leverage effect. Investors only need to invest a small sum to earn a potential return or even higher than that from directly investing in the underlying. However, in picking warrant, investors often get confused with gearing and effective gearing. So, what are the differences between them? Which of them is more indicative?


Gearing only reflects how many times the underlying costs versus the warrant. Its calculation formula is:

Gearing = Underlying Price / (Warrant Price * Conversion Ratio)

For example, the SPC call warrant, SPC RB ECW080526, has a gearing of 7.12 times at point of writing. Then an investment of S$1000 for the warrant will be equivalent to an investment of S$1000 * 7.12 = S$7120 in the underlying. However, gearing do not reflect the relationship between changes in the warrant price and in the underlying price. For example, both CAPITALAND MBL ECW080606 and CAPITALAND BNP ECW080606 have the same maturity on 6th Jun 2008, same entitlement ratio of 3:1 and approximately same implied volatility 44.65% and 46.17% respectively (I know the implied volatility is not really very close but this pair of warrant is one of the closest I can find to illustrate the effect of gearing).The strike price for the warrants are S$5.80 and S$5.98 respectively. The underlying price at point of writing is S$5.85. We can see that the warrant which is further out-of-the-money has a higher gearing of 10.54x compared with 9.51x. If an investor uses the gearing of these two warrants to work out their potential returns, they may be disappointed. The rate of increase/decrease in the warrant price relative to the underlying price is not the same as gearing. When the underlying price increases by 1%, CAPITALAND MBL ECW080606 with a gearing of 9.51x should ideally increase by 9.51% and CAPITALAND BNP ECW080606 with a gearing of 10.54x should ideally increase by 10.54% too. However, in reality, based on the data I have collected for the two warrants, CAPITALAND MBL ECW080606 increases by 20.59% while CAPITALAND BNP ECW080606 does not move a bid with the same price change movement in the underlying. We should look at the effective gearing.

Effective Gearing

Effective gearing reflects the relationship between changes in the warrant price and in the underlying price. Its calculation formula is:

Effective Gearing = Gearing * Delta

In the example I have chosen above, CAPITALAND MBL ECW080606 has an effective gearing of 5.42x while CAPITALAND BNP ECW080606 has an effective gearing of 5.52x. Then, other things being equal, for every 1% change in the underlying price, the warrant price will in theory move by 5.42% and 5.52% respectively. In my not so perfect example here, because the implied volatility for both warrants are difference which causes the warrant prices to be difference and hence the difference in Effective Gearing. In conclusion, when you invest in warrants, you should look to their effective gearing, not gearing, as a reference for their risk/return performance. Just remember that a high effective gearing can give you a higher leverage but it also means it will fall faster too when the market is in not in favor of your direction of your warrant.

Relationship between maturity and effective gearing

Maturity is negatively related to effective gearing. If we have two warrants with the same strike price but different maturity dates, the one with a longer maturity has a lower effective gearing than the other. This is because that the one with a shorter maturity has a lower time value, and thus a higher effective gearing.

ITM/OTM and effective gearing

Further OTM warrants have a higher effective gearing, because their gearing levels are higher. So, if we have two call warrants with the same maturity but different strike prices, the further OTM one will have a higher effective gearing.
One point that must be stressed here is that although the leverage effect is the biggest appeal of warrants as an investment instrument, one should never blindly go after high returns. While it is true that, generally, a higher effective gearing means a higher potential return, if you are too eager to chase after those OTM warrants which are about to expire, the risk involved can be unaffordable.

These warrants are usually less than one month away from maturity, with an over 10% gap between the strike price and the underlying price, which is extremely out of the money.

By now, most readers must have understood that one should look to the effective gearing to predict the size of change in the warrant price for every 1% change in the underlying price.

Yet, one should note that effective gearing can only reflect the theoretical change in the warrant price in response to a given amount of change in the underlying price in the near term. In fact, when the underlying price changes, the delta and gearing levels will change to, which in turn affect the effective gearing. Besides, the formula for effective gearing is based on the assumption that all other things being equal (such as implied volatility, interest rate and market supply and demand). Hence, in case these factors vary, the warrant price may fail to rise in the way suggested by the effective gearing even in the short term.

In general, premium and effective gearing go up and down together. So, a low-premium warrant has a low effective gearing, and the same goes for the opposite. In the case of a short term ITM warrant, although it carries a high delta, its effective gearing is low due to the high price tag and thus, a low gearing. Mind you, warrant trading is mainly about the leverage effect. When the effective gearing is too low, it does not mean much to invest in the warrant, which only gives you a slightly enlarged return when the underlying price moves. Yet, you are not facing less risk associated with the shortening maturity and changes in implied volatility. The risk and return are out of proportion. Besides, although such warrants have a low premium, they are not suitable for investors with a short term perspective. For a more appropriate strategy, you should first identify your target underlying and short list the relevant warrants with a comfortable effective gearing. Then, simply compare the candidates based on their implied volatility to select your right warrant.

I have been very busy this Chinese Lunar New Year and is unable to blog that regularly. I will be posting more regularly on my upcoming posts. :)

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