Pricing a European Option using Simulaitons - vba

Question

I have created a user form that allows the user to change the various variables involved in pricing an option (Exercise Price, volatility..etc) along with allowing the user to change the simulations needed to arrive at the Price (or mean price in this case). However, I am unable to call the public subs within my code once I click the OK Button. Any suggestions on what I'm doing wrong would be greatly appreciated. [I have also included a picture of my user form below]
Option Explicit
Private cancel As Boolean
Public Function ShowInputsDialog(currentPrice As Single, _
exercisePrice As Single, riskfreeRate As Double, _
volatility As Single, duration As Single, simulation As Double) As Boolean
Call Initialize
Me.Show
If Not cancel Then
'Capture the other inputs.
currentPrice = txtCurrentPrice.Text
exercisePrice = txtExercisePrice.Text
riskfreeRate = txtRiskfreeRate.Text
volatility = txtVolatility.Text
duaration = txtDuration.Text
simulation = txtSimulation.Text
ShowInputsDialog = Not cancel
Unload Me
End Function
Public Sub ErrorCheck()
' Perform error checking for user inputs.
If IsNumeric(currentPrice) = False Or currentPrice < 0 Then
MsgBox ("Please enter a numeric value for the Current Price")
End If
If IsNumeric(exercisePrice) = False Or exercusePrice < 0 Then
MsgBox ("Please enter a positive numeric value for the exercise price")
End If
If IsNumeric(riskfreeRate) = False Then
MsgBox ("Please enter a numerical value for the risk-free rate")
End If
If IsNumeric(volatility) = False Then
MsgBox ("Please enter a numerical value for the Standard deviation")
End If
If IsNumeric(duration) = False Then
MsgBox ("Please enter a numerical valye for duration")
End If
End Sub
Public Sub Call_Eur(currentPrice As Single, _
exercisePrice As Single, riskfreeRate As Double, _
volatility As Single, duration As Single, simulation As Double)
Dim stockPrice As Single
Dim CallcashflowTermination As Single
Dim PutcashflowTermination As Single
Dim CalldiscountedValue As Double
Dim PutdiscountedValue As Double
Dim i As Integer
Dim CallMean As Double
Dim PutMean As Double
Dim arrayCallPrice() As Integer
Dim arrayPutPrice() As Integer
For i = 1 To simulation
' stock price
stockPrice = currentPrice * Exp((riskfreeRate - 0.5 * volatility ^ 2) * duration + volatility * Application.WorksheetFunction.Norm_Inv(Rnd(), 0, 1) * Sqr(duration))
' option cash flow at termination
CallcashflowTermination = Application.WorksheetFunction.Max(0, stockPrice - exercisePrice)
PutcashflowTerminatio = Application.WorksheetFunction.Funciton.Max(0, exercisePrice - stockPrice)
' discounted value of the option
CalldiscountedValue = CallcashflowTermination * Exp(-duration * riskfreeRate)
PutdiscountedValue = PutcashflowTermination * Exp(-duration * riskfreeRate)
arrayCallPrice(i) = CalldiscountedValue
arrayPutPrice(i) = PutdiscountedValue
CallMean = Application.WorsheetFunction.Average(arrayCallPrice)
PutMean = Application.WorksheetFunction.Average(arrayPutPrice)
Next i
MsgBox "The Call option price is " & CallMean & " the Put option price is " & PutMean
End Sub
Private Sub CmdCancel_Click()
Me.Hide
cancel = True
End Sub
Private Sub CmdOK_Click() '<--- ERROR!!!
Call Call_Eur(currentPrice As Single, _
exercisePrice As Single, riskfreeRate As Double, _
volatility As Single, duration As Single, simulation As Double)
End Sub
Private Sub UserForm_Click()
End Sub

Answer 1

BIG RED FLAG!!!!
When calling a subroutine. you need to pass values into it. Not redefine it's parameters.
Private Sub CmdOK_Click() '<--- ERROR!!!
Call Call_Eur(12.50, 13.43, 14, 33.56, 100, 13.67)
End Sub
I prefer removing the parenthesis and not using Call at all.
Private Sub CmdOK_Click() '<--- ERROR!!!
Call_Eur 12.50, 13.43, 14, 33.56, 100, 13.67
End Sub