Equity Asian Option

Table of Contents

An equity Asian option pays on the averaged price of an equity underlying over a set period. The averaging smooths the payoff. ORE models it with the trade type EquityAsianOption. This note records the domain grounding, as ORE documents it in its product catalogue.

1. Identifiers

What a trader books it as, and what to grep for. The codes are the trade type catalogue's, which is what the database enforces.

Field Value
Full name Equity Asian Option
Short name Equity Asian Option
ORE Studio product code EquityAsianOption
Asset class equity
Family Option
ORE trade data node EquityAsianOptionData
ORE documentation eq_asianoption.tex

2. Summary

An equity Asian option is a path-dependent option whose payoff depends on the averaged price of an equity underlying over a pre-set period. The average is arithmetic by default and can be geometric. A fixed- strike form compares the average to a strike. A floating-strike form compares the final price to the average. The container node is EquityAsianOptionData. It holds one OptionData sub-node and an ObservationDates schedule. The container node includes the strike, quantity and underlying.

3. Detail

3.1. What it is

ORE defines the product as follows:

An Equity Asian Option is a path-dependent option whose payoff depends upon the averaged price of an Equity underlying over a pre-set period of time.

Source: ORE User Guide, Products catalogue, eq_asianoption.tex.

3.2. In plain terms

An Asian option looks at the average price instead of the final price. Daily fixings over the observation period build the average. A customer who fears a price spike on one day prefers the average. The payoff is harder to manipulate and cheaper than a vanilla option.

3.3. How it works in ORE

The EquityAsianOptionData node is the trade data container for the EquityAsianOption trade type. It has one OptionData trade component sub-node plus elements specific to the equity Asian option. StrikeData holds the strike in Value and the currency of the underlying and the strike in Currency. Quantity is the number of underlying equities. The node takes one Underlying element with Type set to Equity. The OptionData fields set LongShort, OptionType, PayoffType and the exercise date. PayoffType must be Asian or AverageStrike. The first identifies a fixed-strike Asian payoff and the second a floating-strike payoff. PayoffType2 is optional and takes Arithmetic or Geometric. It defaults to Arithmetic. Exactly one ExerciseDate must be given. Premiums can represent deterministic option premia. Settlement is optional and defaults to the exercise date. ObservationDates holds the Asian observation period as a rules-based or dates-based schedule.

3.4. Mathematical notes

The payoff is Payoff = Quantity x MAX(omega x (A(0,T) - K), 0). A(0,T) is the arithmetic average of the underlying equity spot price over the Asian observation period from start 0 to end T. K is the equity strike price. Omega is 1 for a call option and -1 for a put option. A geometric average is available through PayoffType2. The averaging reduces the volatility that reaches the payoff.

3.5. What moves its value (static sensitivities)

  • The spot price of the underlying equity.
  • The implied volatility of the underlying.
  • The strike and the exercise date.
  • The observation schedule and its remaining fixings.
  • The interest rates and dividends of the underlying.

The average lags the spot. A move near the end of the period moves the average more than a move near the start.

3.6. How the profile ages (dynamic sensitivities)

Each observation date adds a fixing to the average. Early fixings become fixed parts of the average. As the period fills, the average stiffens and the option's effective delta falls. Near the final observation the average is almost known and the option value approaches its settlement value.

3.7. Why a customer would want it

A customer who receives or pays a periodic equity price, such as an average-priced buyback, wants an option on that average. The Asian payoff matches the exposure and costs less than a vanilla option of the same expiry. In ORE Studio a customer books equity Asian options to value them and run sensitivities on the ORE engine.

3.8. Example

ORE's catalogue shows a long call on the average of the S&P 500 index over daily observations:

<Trade id="EquityAsianOption">
  <TradeType>EquityAsianOption</TradeType>
  <Envelope>
    <CounterParty>CPTY_A</CounterParty>
    <NettingSetId>CPTY_A</NettingSetId>
    <AdditionalFields />
  </Envelope>
  <EquityAsianOptionData>
    <Quantity>100</Quantity>
    <Currency>USD</Currency>
    <StrikeData>
      <Value>3100</Value>
      <Currency>USD</Currency>
    </StrikeData>
    <Underlying>
      <Type>Equity</Type>
      <Name>RIC:.SPX</Name>
      <Currency>USD</Currency>
    </Underlying>
    <OptionData>
      <LongShort>Long</LongShort>
      <OptionType>Call</OptionType>
      <PayoffType>Asian</PayoffType>
      <PayoffType2>Arithmetic</PayoffType2>
      <ExerciseDates>
        <ExerciseDate>2020-07-15</ExerciseDate>
      </ExerciseDates>
      <Premiums> ... </Premiums>
    </OptionData>
    <Settlement>2020-07-20</Settlement>
    <ObservationDates>
      <Rules>
        <StartDate>2019-12-27</StartDate>
        <EndDate>2020-07-06</EndDate>
        <Tenor>1D</Tenor>
        <Calendar>US</Calendar>
        <Convention>F</Convention>
        <TermConvention>F</TermConvention>
        <Rule>Forward</Rule>
      </Rules>
    </ObservationDates>
  </EquityAsianOptionData>
</Trade>

Source: ORE User Guide, Products catalogue, eq_asianoption.tex, listing Equity Asian Option data.

4. See also

Emacs 29.3 (Org mode 9.6.15)