NonRecombiningTreeIV

Updated 2024-02-13 19:36:10.240000

Syntax

SELECT [westclintech].[wct].[NonRecombiningTreeIV](
  <@CallPut, nvarchar(4000),>
 ,<@AmEur, nvarchar(4000),>
 ,<@AssetPrice, float,>
 ,<@StrikePrice, float,>
 ,<@TimeToMaturity, float,>
 ,<@RiskFreeRate, float,>
 ,<@DividendRate, float,>
 ,<@Dividend_RangeQuery, nvarchar(max),>
 ,<@Price, float,>
 ,<@NumberOfSteps, int,>)

Description

Use the scalar function NonRecombiningTreeIV to calculate the implied volatility of American or European options paying discrete dividends using a non-recombining tree as suggested in Options, Futures, and Other Derivatives, 8th Edition, by John C. Hull. The NonRecombiningTreeIV calculation creates a new binomial tree at every node where there is a dividend payment, potentially creating millions of nodes and should be used sparingly. Primarily, the NonRecombiningTreeIV function should only be used for American Call options where the dividend is very large in relation to the price of the asset, as the recombining tree calculation for dividend-paying stocks tends to underestimate the theoretical value.

Arguments

@Price

the price of the option. @Price is an expression of type float or of a type that can be implicitly converted to float.

@DividendRate

the annualized, continuously compounded zero-coupon dividend rate over the life of the option, used in addition to the discrete dividends. @DividendRate is an expression of type float or of a type that can be implicitly converted to float.

@RiskFreeRate

the annualized, continuously compounded zero-coupon risk-free rate over the life of the option. @RiskFreeRate is an expression of type float or of a type that can be implicitly converted to float.

@TimeToMaturity

the time to expiration of the option, expressed in years. @TimeToMaturity is an expression of type float or of a type that can be implicitly converted to float.

@Dividend_RangeQuery

a string containing an SQL statement which, when executed, provides the function with the times and amounts of the dividends to be used in the calculation. The results of the SQL must contain exactly two columns, the first being the time value, as a float or as a value that implicitly converts to float, and the second being the dividend amount as float, or as a value that implicitly converts to float. @Dividend_RangeQuery is an expression of type nvarchar or of a type that can be implicitly converted to nvarchar.

@AmEur

identifies the option as being American ('A') or European ('E'). @AmEur is an expression of type nvarchar or of a type that can be implicitly converted to nvarchar.

@CallPut

identifies the option as being a call ('C') or a put ('P'). @CallPut is an expression of type nvarchar or of a type that can be implicitly converted to nvarchar.

@StrikePrice

the exercise price of the option. @StrikePrice is an expression of type float or of a type that can be implicitly converted to float.

@NumberOfSteps

the number of steps in the binomial tree. @NumberOfSteps is an expression of type int or of a type that can be implicitly converted to int.

@AssetPrice

the price of the underlying asset. @AssetPrice is an expression of type float or of a type that can be implicitly converted to float.

Return Type

float

Remarks

@Volatility must be greater than zero (@Volatility > 0).

@TimeToMaturity must be greater than zero (@TimeToMaturity > 0).

@AssetPrice must be greater than zero (@AssetPrice > 0).

@StrikePrice must be greater than zero (@StrikePrice > 0).

@NumberOfSteps must be greater than 1 (@NumberOfSteps > 1).

Negative time values returned by @Dividend_RangeQuery are ignored.

Time values returned by @Dividend_RangeQuery that are greater than @TimeToMaturity are ignored.

If @RiskFreeRate is NULL then @RiskFreeRate is set to zero.

If @DividendRate is NULL then @DividendRate is set to zero.

If @NumberOfSteps is NULL then @NumberOfSteps is set to 100.

To calculate the price and/or Greeks of the option use NONRECOMBININGTREE.

To calculate the implied volatility using proportional dividends (where the dividend is specified with a time and a percentage rather than a monetary value) use PROPORTIONALDIVIDENDSIV.

Examples

Calculate the volatility for an American call option expiring in one year with asset price of 100, a strike price of 100 and a theoretical value of 11.9444. The risk-free rate is 2.75%. A single dividend of 50 will be paid in 10 months' time. The number of steps is 100.

SELECT wct.NonRecombiningTreeIV(   'C',                        --Put/Call
                                   'A',                        --American/European
                                   100,                        --Asset Price
                                   100,                        --Strike Price
                                   1,                          --Time-to-maturity
                                   .0275,                      --Risk-free rate
                                   NULL,                       --Dividend rate
                                   'SELECT 0.83333333333, 50', --Discrete Dividends
                                   11.9444,                    --Price
                                   100                         --Number of Steps
                               ) as VOLATILITY;

This produces the following result.

{"columns":[{"field":"VOLATILITY","headerClass":"ag-right-aligned-header","cellClass":"ag-right-aligned-cell"}],"rows":[{"VOLATILITY":"0.300002"}]}